Effects of the meridional extent of mean equatorial upwelling on atmosphere-ocean coupled instabilities over an unbounded ocean

Yoshinobu Wakata, E. S. Sarachik

Research output: Contribution to journalArticle

3 Citations (Scopus)

Abstract

The large scale instabilities of a coupled atmosphere-ocean system on an unbounded equatorial beta plane are investigated by solving the eigenvalue problem. Special attention is paid to the effect of the basic state inhomogeneity due to the meridional extent of the mean equatorial Upwelling. It is found that if the upwelling region near the equator is meridionally wide, an eastward-propagating mode becomes unstable, while if it is narrow, the second symmetric Rossby mode becomes unstable. In the narrow case, when the atmosphere-ocean coupling is strong, both modes can be unstable. Seeming inconsistencies involving the characteristics of anomaly propagation in some previously published results of atmosphere-ocean coupled models of the ENSO phenomenon may arise from this sensitivity to the meridional width of the basic state upwelling.

Original languageEnglish
Pages (from-to)843-854
Number of pages12
JournalJournal of the Meteorological Society of Japan
Volume70
Issue number5
DOIs
Publication statusPublished - Jan 1 1992
Externally publishedYes

Fingerprint

upwelling
atmosphere
ocean
atmosphere-ocean coupling
atmosphere-ocean system
beta-plane
eigenvalue
inhomogeneity
El Nino-Southern Oscillation
anomaly
effect

All Science Journal Classification (ASJC) codes

  • Atmospheric Science

Cite this

Effects of the meridional extent of mean equatorial upwelling on atmosphere-ocean coupled instabilities over an unbounded ocean. / Wakata, Yoshinobu; Sarachik, E. S.

In: Journal of the Meteorological Society of Japan, Vol. 70, No. 5, 01.01.1992, p. 843-854.

Research output: Contribution to journalArticle

@article{bae25f0f25de4b8bb4f68525125cf2a8,
title = "Effects of the meridional extent of mean equatorial upwelling on atmosphere-ocean coupled instabilities over an unbounded ocean",
abstract = "The large scale instabilities of a coupled atmosphere-ocean system on an unbounded equatorial beta plane are investigated by solving the eigenvalue problem. Special attention is paid to the effect of the basic state inhomogeneity due to the meridional extent of the mean equatorial Upwelling. It is found that if the upwelling region near the equator is meridionally wide, an eastward-propagating mode becomes unstable, while if it is narrow, the second symmetric Rossby mode becomes unstable. In the narrow case, when the atmosphere-ocean coupling is strong, both modes can be unstable. Seeming inconsistencies involving the characteristics of anomaly propagation in some previously published results of atmosphere-ocean coupled models of the ENSO phenomenon may arise from this sensitivity to the meridional width of the basic state upwelling.",
author = "Yoshinobu Wakata and Sarachik, {E. S.}",
year = "1992",
month = "1",
day = "1",
doi = "10.2151/jmsj1965.70.5_843",
language = "English",
volume = "70",
pages = "843--854",
journal = "Journal of the Meteorological Society of Japan",
issn = "0026-1165",
publisher = "社団法人日本気象学会",
number = "5",

}

TY - JOUR

T1 - Effects of the meridional extent of mean equatorial upwelling on atmosphere-ocean coupled instabilities over an unbounded ocean

AU - Wakata, Yoshinobu

AU - Sarachik, E. S.

PY - 1992/1/1

Y1 - 1992/1/1

N2 - The large scale instabilities of a coupled atmosphere-ocean system on an unbounded equatorial beta plane are investigated by solving the eigenvalue problem. Special attention is paid to the effect of the basic state inhomogeneity due to the meridional extent of the mean equatorial Upwelling. It is found that if the upwelling region near the equator is meridionally wide, an eastward-propagating mode becomes unstable, while if it is narrow, the second symmetric Rossby mode becomes unstable. In the narrow case, when the atmosphere-ocean coupling is strong, both modes can be unstable. Seeming inconsistencies involving the characteristics of anomaly propagation in some previously published results of atmosphere-ocean coupled models of the ENSO phenomenon may arise from this sensitivity to the meridional width of the basic state upwelling.

AB - The large scale instabilities of a coupled atmosphere-ocean system on an unbounded equatorial beta plane are investigated by solving the eigenvalue problem. Special attention is paid to the effect of the basic state inhomogeneity due to the meridional extent of the mean equatorial Upwelling. It is found that if the upwelling region near the equator is meridionally wide, an eastward-propagating mode becomes unstable, while if it is narrow, the second symmetric Rossby mode becomes unstable. In the narrow case, when the atmosphere-ocean coupling is strong, both modes can be unstable. Seeming inconsistencies involving the characteristics of anomaly propagation in some previously published results of atmosphere-ocean coupled models of the ENSO phenomenon may arise from this sensitivity to the meridional width of the basic state upwelling.

UR - http://www.scopus.com/inward/record.url?scp=0027085960&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=0027085960&partnerID=8YFLogxK

U2 - 10.2151/jmsj1965.70.5_843

DO - 10.2151/jmsj1965.70.5_843

M3 - Article

AN - SCOPUS:0027085960

VL - 70

SP - 843

EP - 854

JO - Journal of the Meteorological Society of Japan

JF - Journal of the Meteorological Society of Japan

SN - 0026-1165

IS - 5

ER -