Verification of Current Velocities Derived from ARGO floats

• Main Authors: Lee, Chung-hsin, 李忠信
• Other Authors: Huang, Shih-Jen
• Format: Others
• Language: zh-TW
• Published: 2015
• Online Access: http://ndltd.ncl.edu.tw/handle/3mt479

碩士 === 國立臺灣海洋大學 === 海洋環境資訊系 === 104 === In recent ten years, network of global hydrographic observation composed of Argo float array have been extensively utilized for oceanographic research, primarily providing near real-time hydrographic data. However, the ocean current velocities in the surface and in the deep sea can be derived from the variations GPS position when the floats stay in the surface and in the deep sea, respectively. The accuracy of current velocity estimate from above methods remains to be validated. In this study, 10-year shipboard ADCP measurements taken from OR1, OR2 and OR3 were used to validate the surface current velocities derived from Argo floats, which were released from Asia-Pacific Data-Research Center (APDRC). Deep current measurements by Lowered-ADCP conducted from several cruises were used to validate the deep current velocities derived from the Argo floats. Both the two velocity observation was bin-averaged in 1/4o grid. The correlation coefficient between the surface meridional velocities obtained from the ship measurements and the Argo estimate was 0.6. The correlation coefficient between the surface zonal velocities obtained from the ship measurements and the Argo estimate was 0.5. The magnitude of deep current velocity derived from Argo float agreed well with that measured from shipboard ADCP. However, the current direction appeared to disagree, which may be induced by the corruption of the upper ocean currents to the methods estimating the deep current speeds.