海面流场卫星遥感方法综述

Overview on Satellite Remote-sensing Methods for Sea-surface-current Measurement

关键词:  海表面流  流场反演  卫星遥感  合成孔径雷达

Key words:  sea surface currents  current field retrieval  satellite remote sensing  synthetic aperture radar

摘要:

海表面流矢量是海洋和气象领域诸多过程中最基本、最重要的要素,它们对海洋中多种生物过程、化学过程和物理过程都有制约作用,因此,掌握全球范围的海流信息和规律无论是对于海洋学本身的研究,还是与海洋密切相关的渔业、航运等都有重要意义。测量海流比较直接的方式是"现场观测",然而这种方法的空间覆盖范围有限,且观测成本较高。岸基高频地波雷达是专门用来测量沿岸海流的雷达设备,然而其测量的空间范围有限,不能进行全球观测。卫星遥感能够实现低成本、高空间分辨率、以及全球范围的海场测量。本文对海面流场卫星遥感方法进行综述,其中包括多时相示踪物测量法、卫星高度计测量法、合成孔径雷达多普勒中心偏移法、以及合成孔径雷达沿航向干涉法,并对海面流场卫星遥感方法进行展望。

Abstract:

Sea surface currents can impose influences and constraints on oceanic physical processes, chemical processes and biological processes, so the measurement of global seasurface currents is of great significance for the oceanography research or for fisheries, shipping, etc.One direct way of measuring sea currents is the in situ observation.However, this method is generally limited in its spatial coverage due to its high cost.Shore-based high-frequency radar systems are specially designed to map the currents off the coast.However, their coverage, like the in situ observation, is also limited and cannot realize a global scale.Only satellite remote sensors can provide a cost-effective means of monitoring sea surface currents with a global coverage.The objective of this paper is to review several remote-sensing methods for mapping seasurface currents, including the sequential-image feature tracking method, the satellite altimetry method, the synthetic aperture radar (SAR) Doppler centroid shift method, and the SAR along-track interferometry method.Finally, we give an outlook for upcoming technologies for sea-surface-current measurement.