Dominant Forcing Regions of Decadal Variations in the Kuroshio Extension Revealed by a Linear Rossby Wave Model

Abstract

The Kuroshio Extension (KE) is a strong eastward inertial jet in the western North Pacific formed after the Kuroshio separates from the Japanese coast. Since the Kuroshio transports a large volume of warm water from the tropics to the midlatitudes, a huge amount of heat is released from the sea surface over the KE region (Sugimoto & Hanawa, 2011;Tomita & Kubota, 2005). Moreover, a sharp gradient of sea surface temperature (SST) associated with convergence of the KE and the Oyashio Extension (Kida et al., 2015), a cold current flowing north of the KE, can affect stormtrack activity in the overlying atmosphere and the large-scale atmospheric circulation (Nakamura et al., 2004). Because of these effects on the atmosphere, the KE region is supposed to influence weather (

Skillful Multiyear Prediction of the Kuroshio and Gulf Stream Jets and Eddy Activity

“…Several studies have explored the potential predictability of low‐frequency variations in WBC jets using various approaches with different complexities, from simplified conceptual models (Qiu et al., 2014; Schneider & Miller, 2001; Tamura & Tozuka, 2023) to perfect model experiments using an eddy‐resolving ocean general circulation model (OGCM) (Nonaka et al., 2012; Taguchi et al., 2007). These studies have demonstrated that not only the large‐scale signatures of WBC jets, such as area‐averaged sea surface height (SSH) fields, but also jet speed are potentially predictable with a lead time of a few years.…”