PIES와 위성고도계로 쿠로시오직류 해역에서 관측한 해수면 높이 변동

Abstract

AVISO along-track and gridded sea level anomaly (SLA) products are compared with in-situ sea surface height anomaly (SSHA) measurements from an array of 43 pressure-recording inverted echo sounders (PIESs) in the Kuroshio Extension. The bottom pressure and acoustic echo time measurements from PIES are used to estimate, respectively, the mass-loading and steric height components in SSHA. Overall, along-track SLA and PIES-derived SSHA agree well each other with mean correlation coefficient of 0.97. Comparisons show that the mass-loading component is relatively small in this region. The AVISO up-to-date gridded product, which merges all available satellite measurements of Jason-1, Envisat, Geosat Follow-On, and TOPEX/Poseidon, shows better correlations and smaller rms differences than the AVISO reference gridded product, which merges only Jason-1 and Envisat. Gridded products exhibit low correlation (0.75−0.9) with PIES-derived SSHA in a region where the SSHA have relatively high energy at periods shorter than the Nyquist frequency of Jason-1 (20 days).