Comparative analysis of significant wave height between a new Southern Ocean buoy and satellite altimeter

Abstract

In-situ observation is restricted by the strong wind and waves in the Southern Ocean. A Westerlies Environmental Monitoring Buoy (WEMB) was firstly deployed in the Southern Ocean during China's 35th Antarctic Expedition, facilitating further understanding of the oceanic environmental characteristics of this region. With the development of technology and the improvement of data processing methods, the accuracy of satellite altimeter products is constantly improved, thus making it possible to inspect and evaluate the in-situ observation data. Based on the L3 products of multiple satellite altimeters, this paper analyzes and corrects the significant wave height (SWH) data of WEMB by means of data matching, error statistics, and linear least-squares fitting. Through this study, the authors obtained the following results. The effect of gravitational acceleration changes with latitude on SWH accuracy is fairly small. Due to the low response of WEMB to high-frequency waves, there is a systematic deviation. A feasible correction method is therefore proposed to improve the SWH accuracy of WEMB. The temporal variation of the corrected SWH is highly consistent with that of the 10 m wind during the observation period, and its average value reaches 3.8 m.摘要中国于2019年第35次南极考察中, 首次在南大洋布放了锚系实时综合观测浮标 (西风带海洋环境监测浮标, WEMB), 为深入了解此海区的海洋环境变化提供了宝贵资料.国家海洋技术中心WEMB研究团队基于AVISO公开发布的多颗卫星高度计L3产品, 通过数据配对,误差统计和最小二乘线性拟合等方法, 对西风带海洋环境监测浮标的有效波高数据误差进行了分析与校正.校正后的浮标有效波高统计显示西风带常年处于大浪以上海况, 观测期间内57%处于巨浪海况, 并且伴随有高度相关的大风天气.