Initialized decadal prediction for transition to positive phase of the Interdecadal Pacific Oscillation

• Published in: Nature communications Vol. 7; no. 1; pp. 11718 - 7
• Main Authors: Meehl, Gerald A., Hu, Aixue, Teng, Haiyan
• Format: Journal Article
• Language: English
• Published: London Nature Publishing Group UK 02.06.2016; Nature Publishing Group; Nature Portfolio
• Subjects: 704/106/829/2737; atmospheric moisture; Climate change; climate variability; early-2000s hiatus; El Nino; ENVIRONMENTAL SCIENCES; GEOSCIENCES; Global temperatures; Global warming; heat-content; Humanities and Social Sciences; intensification; mid-1970s shift; multidisciplinary; Ocean currents; ocean recharge mechanism; Science; Science (multidisciplinary); Sea level; Sea surface temperature; Southern Oscillation; Upper ocean; warming hiatus; wind
• ISSN: 2041-1723; 2041-1723
• DOI: 10.1038/ncomms11718

The negative phase of the Interdecadal Pacific Oscillation (IPO), a dominant mode of multi-decadal variability of sea surface temperatures (SSTs) in the Pacific, contributed to the reduced rate of global surface temperature warming in the early 2000s. A proposed mechanism for IPO multidecadal variability indicates that the presence of decadal timescale upper ocean heat content in the off-equatorial western tropical Pacific can provide conditions for an interannual El Niño/Southern Oscillation event to trigger a transition of tropical Pacific SSTs to the opposite IPO phase. Here we show that a decadal prediction initialized in 2013 simulates predicted Niño3.4 SSTs that have qualitatively tracked the observations through 2015. The year three to seven average prediction (2015–2019) from the 2013 initial state shows a transition to the positive phase of the IPO from the previous negative phase and a resumption of larger rates of global warming over the 2013–2022 period consistent with a positive IPO phase. The phase of the Interdecadal Pacific Oscillation (IPO) impacts global temperatures. Here, the authors show that a build-up of off-equatorial western tropical Pacific heat content allows ENSO events to trigger IPO phase changes, with a predicted switch to a positive IPO for 2015–2019 and larger warming trends.