論文

査読有り
2017年

A Precursor of the Monthly-Mean Large-Scale Atmospheric Circulation Anomalies over the North Pacific

SOLA
  • Tomohiko Tomita
  • ,
  • Tsuyoshi Yamaura

13
開始ページ
85
終了ページ
89
記述言語
英語
掲載種別
研究論文(学術雑誌)
DOI
10.2151/sola.2017-016
出版者・発行元
METEOROLOGICAL SOC JAPAN

The North Pacific shows dominant monthly-mean large-scale atmospheric circulation anomalies, even after removing the variabilities of the Northern Hemisphere annular mode and the El Nino/Southern Oscillation. This work examines the precursors and their development for these residual anomalous circulations by applying objective reanalysis data to empirical orthogonal function (EOF) analysis. The first EOF mode (EOF1) features a monopole, while a dipole characterizes the second EOF mode (EOF2) over the North Pacific. Transient eddies (TEs) interactively induce the two EOF modes.The precursors of EOF1 and EOF2 are detected in the anomalies of one month earlier; these are the systematic zonal bands detected in surface temperature and baroclinic instability (BI) in the lower troposphere over Eurasia and North America. The BI anomalies further extend into the central North Pacific at different latitudes between EOF1 and EOF2. Coherent zonal bands also appear in the geopotential height anomalies of upper troposphere. Such zonal bands reflect the ovalization of Arctic circumpolar circulation with different continent-ward shifts of the longer axis. The direction of this shift determines which EOF mode develops by the following month through the guided activation of TEs at a designated latitude over the North Pacific.

リンク情報
DOI
https://doi.org/10.2151/sola.2017-016
Web of Science
https://gateway.webofknowledge.com/gateway/Gateway.cgi?GWVersion=2&SrcAuth=JSTA_CEL&SrcApp=J_Gate_JST&DestLinkType=FullRecord&KeyUT=WOS:000402299900001&DestApp=WOS_CPL
ID情報
  • DOI : 10.2151/sola.2017-016
  • ISSN : 1349-6476
  • Web of Science ID : WOS:000402299900001

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