Mesoscale Thermal Variability in the Vicinity of the Kuroshio Extension

Abstract

Two multi-ship XBT surveys have acquired data on the mesoscale temperature structure in the region of the Kuroshio Extension. Thermal sections and maps illustrate cold features in the thermocline near 31°N and warm ones near 37°N. Isotherm displacement spectra exhibit a plateau of order 103 m2 per cycle per kilometer for scales longer than 500 km, and they roll off between the second and third inverse power of the wavenumber for shorter scales. There is a significant decrease in spectral amplitude south of about 31°N.