Midwinter Reversal of the Atmospheric Anomalies Caused by the North Pacific Mode‐Related Air‐Sea Coupling

Abstract

In past decades, several prominent sea surface temperature anomaly (SSTA) modes in midlatitude North Pacific are identified on decadal-to-interdecadal timescale, that is,

Effect of Oceanic Stochastic Forcing on Wintertime Atmospheric Decadal Variability Over Midlatitude North Pacific

“…Processes of oceanic impact on atmospheric circulations in midlatitudes are more complicated than those in the tropics. Different from the moisture condensation latent heat release‐driven processes in the tropics (Gill, 1980; Hoskins & Karoly, 1981; Jin & Hoskins, 1995; Matsuno, 1966; Sardeshmukh & Hoskins, 1988), the midlatitude SSTAs can influence the mid‐to‐high level atmospheric circulation primarily through the atmospheric transient eddy forcing (Chen et al., 2020; Fang et al., 2021; Fang & Yang, 2011; Tao et al., 2022). The atmospheric transient eddy activity called “storm track” is most active over the midlatitude oceans (Blackmon et al., 1977), and it can efficiently redistribute heat and momentum throughout the troposphere (Holopainen et al., 1982; Hoskins et al., 1983; Lee & Kim, 2003).…”

Wintertime ocean-atmosphere interaction processes associated with the SST variability in the North Pacific subarctic frontal zone

“…Our previous work Fang and Yang (2016) atmosphere system. This hypothesis has been confirmed by the later observational, theoretical and modeling studies (Wang et al 2017;Chen et al 2020;Tao et al 2020Tao et al , 2022Zhang et al 2020;Fang et al 2022). However, the above midlatitude ocean-atmosphere interaction mechanism is proposed based on the simultaneous correlation of seasonal-mean data that is already an equilibrium state after air-sea adjustment.…”

“…According to the equation, three types of physical processes can lead to the change of SST, i.e., the net surface turbulent heat flux, the horizontal Ekman advection driven by surface wind stress, and the vertical entrainment. Note that the advection of geostrophic flow, which is proven to be unimportant by previous studies (Fang and Yang 2016; Yao et al 2017;Tao et al 2022), has been neglected in the equation.…”

“…The systematical transportations of heat, moisture and momentum by transient eddies can in turn drive and maintain the midlatitude mean atmospheric circulations (Chang and Orlanski 1993;Chang et al 2002;Ren et al 2010;Sampe et al 2010;Xiang and Yang 2012;Nie et al 2013Nie et al , 2014Fang and Yang 2016;Wang et al 2017;Tao et al 2020). Therefore, the midlatitude atmospheric circulation is both thermal-and transient eddy-driven, and the midlatitude SST anomalies can affect the atmosphere by changing both the diabatic heating and the transient eddy feedback (Nakamura et al , 2008Nonaka et al 2009;Taguchi et al , 2012Sampe et al 2010;Hotta and Nakamura 2011;Fang and Yang 2016;Tao et al 2020Tao et al , 2022.…”

Role of North Atlantic Tripole SST in Mid‐Winter Reversal of NAO

“…The detailed calculations of Q d , Q eddy , and F eddy and their induced geopotential tendency and zonal wind tendency refer to Text S1 in Supporting Information . In midlatitudes, the atmospheric circulation can induce basin‐scale SST anomalies by surface turbulent heat flux, meridional current advection, and Ekman pumping (Fang & Yang, 2016; Qiu, 2000; Qiu & Kelly, 1993; Tao et al., 2022; Yao et al., 2017), as described in Text S2 of the Supporting Information . Wave activity flux is used to illustrate the propagation of stationary or migratory quasi‐geostrophic wave (Takaya & Nakamura, 2001).…”