Relating the Strength of the Tropospheric Biennial Oscillation (TBO) to the Phase of the Interdecadal Pacific Oscillation (IPO)

TitleRelating the Strength of the Tropospheric Biennial Oscillation (TBO) to the Phase of the Interdecadal Pacific Oscillation (IPO)
Publication TypeJournal Article
Year of Publication2012
JournalGeophysical Research Letters
NumberL20716
Date Published10/2012
Abstract / Summary

Coupled air-sea processes in the Indo-Pacific region associated with the tropospheric biennial oscillation (TBO) should make the Indian monsoon and El Nino/Southern Oscillation (ENSO) perfectly biennial, thus providing considerable skill for climate predictions a few years in advance.  However, sometimes the Indo-Pacific climate system is more biennial than others, raising the question as to what is causing the strength of the TBO to wax and wane.  We show that multi-decadal variability associated with the Interdecadal Pacific Oscillation (IPO) affects the nature of year-to-year variability of the TBO.  Thus when tropical Pacific sea surface temperatures (SSTs) are somewhat warmer than normal, as they were from the late-1970s to the late-1990s, the Indo-Pacific climate system is less biennial and the TBO is weak.  Conversely, when the IPO is in a negative phase with somewhat cooler than normal SSTs, as it was just prior to the 1970s and after the late-1990s, the TBO is stronger and the monsoon-ENSO system is more biennial.  This implies that if the phase of the IPO could be predicted in a decadal climate prediction system, there would be added short-term year-to-year prediction skill for the monsoon-ENSO system in the Indo-Pacific region. 

DOI10.1029/2012GL053386
Journal: Geophysical Research Letters
Year of Publication: 2012
Number: L20716
Date Published: 10/2012

Coupled air-sea processes in the Indo-Pacific region associated with the tropospheric biennial oscillation (TBO) should make the Indian monsoon and El Nino/Southern Oscillation (ENSO) perfectly biennial, thus providing considerable skill for climate predictions a few years in advance.  However, sometimes the Indo-Pacific climate system is more biennial than others, raising the question as to what is causing the strength of the TBO to wax and wane.  We show that multi-decadal variability associated with the Interdecadal Pacific Oscillation (IPO) affects the nature of year-to-year variability of the TBO.  Thus when tropical Pacific sea surface temperatures (SSTs) are somewhat warmer than normal, as they were from the late-1970s to the late-1990s, the Indo-Pacific climate system is less biennial and the TBO is weak.  Conversely, when the IPO is in a negative phase with somewhat cooler than normal SSTs, as it was just prior to the 1970s and after the late-1990s, the TBO is stronger and the monsoon-ENSO system is more biennial.  This implies that if the phase of the IPO could be predicted in a decadal climate prediction system, there would be added short-term year-to-year prediction skill for the monsoon-ENSO system in the Indo-Pacific region. 

DOI: 10.1029/2012GL053386
Citation:
Meehl, GA, and JM Arblaster.  2012.  "Relating the Strength of the Tropospheric Biennial Oscillation (TBO) to the Phase of the Interdecadal Pacific Oscillation (IPO)."  Geophysical Research Letters.  https://doi.org/10.1029/2012GL053386.