Deep ocean variability in the Luzon Strait (LS) is critical to water exchange between the South China Sea (SCS) and the Pacific Ocean. Based on satellite observations and numerical simulations, we propose a remote linkage between the LS and the Kuroshio Extension (KE), mediated by topographic Rossby waves (TRWs). Analyses of information flow and coherence demonstrate significant correlations in bottom pressure variability between the LS and KE regions spanning from intraseasonal to quasi-decadal scales, with time lags of 2-3 months closely linked to the propagation of TRWs. Moreover, the energetics analysis suggests that the energy sources of these TRWs are associated with intense surface disturbances in the KE region through vertical pressure work. Because the vertical coupling processes extend from the continental slope to the interior basin, the bottom responses to surface disturbances are coherent across the entire KE region, which accounts for the remote linkage between the LS and KE regions despite different depths. Our results provide a new insight into the physical mechanisms underlying abyssal variability in the LS, highlighting the potential role of the KE region in modulating water exchange between the SCS and the Pacific Ocean.

暂无