[A-CG33] 熱帯におけるマルチスケール大気海洋相互作用

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

*今田 由紀子^1,2、建部 洋晶³ (1.気象庁気象研究所、2.東京大学大気海洋研究所、3.海洋研究開発機構)

キーワード：熱帯太平洋十年規模変動

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.