The role of global circumnavigating mode in the MJO initiation and propagation

Fuqing Zhang, Sourav Taraphdar, Shuguang Wang

Research output: Contribution to journalArticle

9 Citations (Scopus)

Abstract

A series of convection-permitting regional-model simulations are used to study the influences of intraseasonal forcings from the periphery of the tropical Indian Ocean on the October 2011 Madden-Julian Oscillation (MJO) event well observed during the Dynamics of the Madden-Julian Oscillation field campaign. These sensitivity experiments demonstrate the predominant role of a global circumnavigating mode in the initiation and propagation of this MJO event, although the regional framework would not completely rule out influences from the extratropics through the western boundary of the model domain. It is found that filtering out intraseasonal forcing leads to the absence of Kelvin waves, which may reduce moisture transport and weakened lower level convergence at the leading edge of the westerlies and further leads to diminishing MJO signatures in these sensitivity experiments. Meanwhile, for the same regional domain initiated 2 weeks before the onset of the MJO convection, there is little impact of whether or not the global MJO signals retained in the initial conditions. On the other hand, the removal of the global MJO signals from the lateral boundary conditions will not affect the propagation of the MJO after it has been initiated in the regional model domain.

Original languageEnglish (US)
Pages (from-to)5837-5856
Number of pages20
JournalJournal of Geophysical Research
Volume122
Issue number11
DOIs
StatePublished - Jan 1 2017

Fingerprint

Madden-Julian Oscillation
Madden-Julian oscillation
propagation
Moisture
Experiments
Boundary conditions
convection
Kelvin waves
Kelvin wave
Indian Ocean
sensitivity
leading edges
moisture
simulation models
boundary condition
Convection
experiment
signatures
boundary conditions

All Science Journal Classification (ASJC) codes

  • Geophysics
  • Forestry
  • Oceanography
  • Aquatic Science
  • Ecology
  • Water Science and Technology
  • Soil Science
  • Geochemistry and Petrology
  • Earth-Surface Processes
  • Atmospheric Science
  • Space and Planetary Science
  • Earth and Planetary Sciences (miscellaneous)
  • Palaeontology

Cite this

Zhang, Fuqing ; Taraphdar, Sourav ; Wang, Shuguang. / The role of global circumnavigating mode in the MJO initiation and propagation. In: Journal of Geophysical Research. 2017 ; Vol. 122, No. 11. pp. 5837-5856.
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The role of global circumnavigating mode in the MJO initiation and propagation. / Zhang, Fuqing; Taraphdar, Sourav; Wang, Shuguang.

In: Journal of Geophysical Research, Vol. 122, No. 11, 01.01.2017, p. 5837-5856.

Research output: Contribution to journalArticle

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