North Atlantic as a Trigger for Pacific‐Wide Decadal Climate Change

Abstract

The Interdecadal Pacific Oscillation (IPO) (Power et al., 1999), also called the Pacific Decadal Oscillation (Mantua et al., 1997;Zhang et al., 1997), is a pan-Pacific dominant mode of decadal climate variability, characterized by a tripolar pattern with one-sign SST anomalies in the tropical Pacific and opposite-sign SST anomalies in the western-central regions of North and South Pacific. Its Atlantic counterpart, the Atlantic Multidecadal Variability (AMV) (Ruprich-Robert et al., 2017), which is generally referred to as the Atlantic Multidecadal Oscillation (Kushnir, 1994;Schlesinger & Ramankutty, 1994), is manifested as a multidecadal variation of same-sign SST anomalies in the whole North Atlantic (Ting et al., 2009;Trenberth & Shea, 2006). Both the IPO and AMV have experienced several phase shifts over the past century, with profound impacts on regional and global climate. In particular, the warm-phase AMV and cold-phase

Decadal to Multidecadal Variability of the Western North Pacific Subtropical Front and Countercurrent

“…The teleconnection by AMO is the origination for the physical processes discussed in the present study. Previous studies have shown that the AMO‐like forcing could induce pressure, wind and air‐sea heat flux anomalies in the North Pacific Ocean and then drive the oceanic environment changes (e.g., Gong et al., 2020; Sun et al., 2017; L. Wu et al., 2008; Yao et al., 2021; Zhang & Delworth, 2007). The possible mechanism for this interbasin teleconnections is through the atmospheric bridge (Li et al., 2016; Meehl et al., 2021; Z. Zhang et al., 2018).…”

Optimal Growth of IPV Lags AMV Modulations by up to a Decade

“…(a) The AMV can modulate the North Pacific Subtropical High (Lyu et al., 2017), which in turn leads to wind anomalies along the NPMM region and influences SST there (Yu et al., 2015). (b) The AMV modulates the Pacific Walker Circulation and trade winds along the equatorial Pacific (Kucharski et al., 2016; McGregor et al., 2014; Meehl, Hu, et al., 2021; Ruprich‐Robert et al., 2017; Yao et al., 2021), which generates thermocline adjustments for developing the IPV (Li et al., 2016). Thus, there is a possibility that the AMV can provide additional skill for IPV decadal prediction.…”

“…Previous studies have shown the AMV modulations on the IPV (Dong et al., 2006; Kucharski et al., 2016; Li et al., 2016; McGregor et al., 2014; Meehl, Hu, et al., 2021; Ruprich‐Robert et al., 2017; Yao et al., 2021), but its importance on IPV decadal prediction remains unclear. Chikamoto et al.…”

“…However, LIMs constructed by decadal EOF modes in this paper cannot exclude the nonlinear rectification of ENSO (Kim & Kug, 2020). To what extent the IPV is independent of ENSO needs more studies. Previous studies have shown the AMV modulations on the IPV (Dong et al., 2006; Kucharski et al., 2016; Li et al., 2016; McGregor et al., 2014; Meehl, Hu, et al., 2021; Ruprich‐Robert et al., 2017; Yao et al., 2021), but its importance on IPV decadal prediction remains unclear. Chikamoto et al.…”

“…Hence, the limited predictability of ENSO (lower than 2 years; e.g., Ham et al., 2019) may limit IPV decadal predictability. On the other hand, other factors, such as the Atlantic Multidecadal Variability (AMV; Trenberth & Shea, 2006), which demonstrate generally stronger predictability than the IPV (Kirtman et al., 2013; Yeager et al., 2012; Yeager & Robson, 2017), can modulate the IPV phase reversion and development (Dong et al., 2006; Kucharski et al., 2016; Li et al., 2016; McGregor et al., 2014; Meehl, Hu, et al., 2021; Ruprich‐Robert et al., 2017; Yao et al., 2021). Such effect may be important for IPV decadal prediction.…”