ENSO modulation of tropical Indian Ocean subseasonal variability

Eunsil Jung, Benjamin Kirtman

Research output: Contribution to journalArticle

2 Citations (Scopus)

Abstract

In this study, we use 30 years of retrospective climate model forecasts and observational estimates to show that El Niño/Southern Oscillation (ENSO) affects the amplitude of subseasonal variability of sea surface temperature (SST) in the southwest Indian Ocean, an important Tropical Intraseasonal Oscillation (TISO) onset region. The analysis shows that deeper background mixed-layer depths and warmer upper ocean conditions during El Niño reduce the amplitude of the subseasonal SST variability over Seychelles-Chagos Thermocline Ridge (SCTR), which may reduce SST-wind coupling and the amplitude of TISO variability. The opposite holds for La Niña where the shallower mixed-layer depth enhances SST variability over SCTR, which may increase SST-wind coupling and the amplitude of TISO variability.

Original languageEnglish (US)
Pages (from-to)12,634-12,642
JournalGeophysical Research Letters
Volume43
Issue number24
DOIs
StatePublished - Dec 28 2016

Fingerprint

Southern Oscillation
Indian Ocean
sea surface temperature
intraseasonal variations
Seychelles
modulation
thermoclines
oscillation
thermocline
mixed layer
ridges
climate models
upper ocean
forecasting
climate modeling
oceans
estimates

Keywords

  • air-sea coupling
  • amplitude of subseasonal variability
  • mixed-layer depth

ASJC Scopus subject areas

  • Geophysics
  • Earth and Planetary Sciences(all)

Cite this

ENSO modulation of tropical Indian Ocean subseasonal variability. / Jung, Eunsil; Kirtman, Benjamin.

In: Geophysical Research Letters, Vol. 43, No. 24, 28.12.2016, p. 12,634-12,642.

Research output: Contribution to journalArticle

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