Precise measurement of sea surface dynamic height by GPS kinematic survey and its application to Kuroshio studies

GPS运动学精确测量海面动态高度及其在黑潮研究中的应用

基本信息

批准号：
09440165
负责人：
HANAWA Kimio
金额：
$ 3.78万
依托单位：
TOHOKU UNIVERSITY
依托单位国家：
日本
项目类别：
Grant-in-Aid for Scientific Research (B)
财政年份：
1997
资助国家：
日本
起止时间：
1997 至 1999
项目状态：
已结题

来源：
https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-09440165/
关键词：
Kuroshio GPS dynamic height XBT ADCP mesoscale eddy Subtropical Mode Water monsoon 中規模渦高度計海面高度 GPS(汎地球測位システム)海面力学高度 TOPEX POSEIDON衛星 ADCD 潮流

项目摘要

In the present study, the following three items were carried out : (1) Precise measurement of sea surface height by GPS kinematic survey installed on a ferry boat, (2) clarification of mesoscale eddies in the studied area using ADCP data and TOPEX/POSEIDON altimeter data and (3) water mass structure and its variation in the studied area using the archived temperature data. Main results can be summarized as follows.(1) Using the ferry Ogasawara Maru which shuttles between Tokyo and Ogasawara Islands, we carried out the GPS kinematic survey in September 1999. We could obtain the data suitable for analysis when the distance of two GPS stations (the reference station and the ferry) is short (shorter than hundreds km). However, it was found that the distance is relatively longer, the data are not suitable for analysis. From the data obtained when the ferry was anchored at Hutami Port, we could detect the tidal signal with enough accuracy.(2) Using the ADCP data and TOPEX/POSEIDON altimeter data, we analyzed the mesoscale eddies in the Kuroshio recirculation area. We found a plenty of anticyclonic and cyclonic eddies whose diameter is approximately 500km. The temporal scale is estimated to be approximately 80 days. It was suggested these eddies are formed on the Kuroshio Extension area.(3) Using the archived temperature data, we made the gridded temperature data and analyzed interannual variation of subtropical mode water with respect to the strength of wintertime East Asia monsoon. It was found that when the wintertime East Asian monsoon is strong (weak), thick (thin) and cold (warm) subtropical mode water is formed.

在本研究中，进行了以下三项工作：（1）通过安装在渡船上的 GPS 运动学测量精确测量海面高度，（2）利用 ADCP 数据和 TOPEX/POSEIDON 澄清研究区域的中尺度涡流高度计数据和（3）使用存档的温度数据研究区域的水团结构及其变化。主要结果可概括如下：(1)利用往返于东京和小笠原群岛之间的轮渡“小笠原丸”，我们于1999年9月进行了GPS运动学测量。当两个GPS站的距离较远时，我们可以获得适合分析的数据。（参考站和渡轮）很短（短于数百公里）。但发现距离比较远，数据不适合分析。根据渡轮停泊在胡塔米港时获得的数据，我们可以足够准确地探测到潮汐信号。(2)利用ADCP数据和TOPEX/POSEIDON高度计数据，对黑潮回流区的中尺度涡流进行了分析。我们发现了大量的反气旋和气旋涡流，其直径约为500公里。时间尺度估计约为80天。推测这些涡流是在黑潮延伸区形成的。(3)利用档案温度数据,制作了网格化温度数据并分析了副热带模式水相对于冬季东亚季风强度的年际变化。研究发现，冬季东亚季风强（弱）、厚（薄）、冷（暖）的副热带模态水形成。