基于海啸感应电磁场的海啸监测研究与应用现状

Research and Application Status of Tsunami Monitoring Based on Tsunami Induced Electromagnetic Field

早期的海啸监测系统主要依赖地震监测网或海底压力计阵列网,但都存在诸如建设和维护成本高、监测范围有限等问题。对海啸的实际观测和模拟发现,广泛分布的海底电缆能够反映海啸运动产生的感应电磁场,由此发展出了更为便捷和经济的海啸感应电磁场监测方法。本文介绍了海啸感应电磁场的理论推导过程、不同海啸速度模型,以及对不同海底地形类型的海啸感应电磁场解析解的研究进展。对比分析海啸感应电磁场的电压、扰动磁场、矢量电磁场三种海啸电磁监测方法的优缺点后认为,矢量电磁场监测具有测量海啸传播方向的优势,利用矢量电磁测量结合现有的海啸监测系统能更快更准更实时地预警海啸。

The early tsunami monitoring system relies mainly on seismic monitoring network or subsea manometer array network.However,these methods all have the problems such as high cost of construction and maintenance and limited monitoring scope,and so on.From actual observations and numerical simulations of tsunami,it has been found that the widely distributed subsea cables can reflect the induction electromagnetic field produced by the movement of tsunami,from which more convenient and economical methods for monitoring the tsunami-induced electromagnetic field(TIEF)are developed.The theoretical derivation process of the TIEF is introduced and the analytical solutions of the TIEF under the cases of different tsunami velocity models and seafloor topographical types are studied.By comparing the merits and faults of monitoring the voltage,disturbance magnetic field and vector electromagnetic field of TIEF,it is found that the monitoring of the vector electromagnetic field has the advantage of measuring the propagation direction of tsunami and the application of the vector electromagnetic field monitoring together with the existing tsunami monitoring system can make the warning of tsunami faster,more accurate and more real time.