Method for processing XCP data with improved accuracy

Abstract. An expendable current profiler (XCP) is a device used for monitoring ocean currents. In this study, we focus on the technology available for processing XCP data and propose a more accurate method for calculating the current velocity from the nanovolt-scale current-induced electric field measured using an XCP. In order to confirm the accuracy of the proposed data processing method, a sea test was performed in the South China Sea region, wherein, for the first time in China, ocean current and electric-field data were collected from the sea surface to a depth of 1000 m using an XCP. The current-data processing method described herein was used to determine the eastward and northward relative velocity components of the current from the measured data, which were then compared with the current data obtained using an acoustic Doppler current profiler, in order verify the accuracy of the measurements as well as that of the data processing method.