[A-CG33] Multi-scale ocean-atmosphere interaction in the tropics

[ACG33-P06] Recent status of tropical Pacific decadal variability (TPDV) of South Pacific origin

*Yukiko Imada^1,2, Hiroaki Tatebe³ (1.Meteorological Research Institute, Japan Meteorological Agency, 2.Atmosphere and Ocean Research Institute, the University of Tokyo, 3.Japan Agency for Marine-Earth Science and Technology)

Keywords:Tropical Pacific Decadal Variability (TPDV)

There are various hypotheses that explain tropical Pacific decadal variability (TPDV). One of them is the so-called VbarT’ mechanism, that is, sea temperature anomaly advected by mean ocean current. Tatebe et al. (2013) showed that the VbarT’ in the South Pacific subsurface ocean has an important role in maintaining TPDV. This subsurface temperature anomaly in the South Pacific Ocean can be a good precursor to know the TPDV status in real time, whereas general TPDV indices defined by SST are difficult to separate from ongoing ENSO. In this study, we assessed the recent status of TPDV using the subsurface isopycnal temperature anomalies in the South Pacific Ocean. It implies that the current phase is the near end of the negative TPDV that has been going on since the 2000s.