Biweekly Periodic Deep Flow Variability on the Slope Inshore of the Kuril–Kamchatka Trench

Abstract

Five long-term current records are analyzed to investigate the temporal variability for deep flows, from a single mooring fitted with two current meters on the slope inshore of the southern end of the Kuril?Kamchatka Trench southeast of Cape Erimo, where the Oyashio and a deep western boundary current are considered to flow southwestward together. At 3000 m the spectral peaks of eddy kinetic energy were found at about 2 weeks in all current records. The flow variability with period of 2 weeks at 3000 m was more energetic than that at 1000 m. By applying topographic Rossby wave theory, this variability is thought to be due to bottom-trapped topographic Rossby waves.