走航式海洋多参数剖面测量系统(moving vessel profiler, MVP)是一种集成程度和自动化程度都较高的海洋调查设备,能对海洋多要素进行同时观测,获得水平方向的高分辨率数据资料。由于温度和电导率传感器响应时间的不匹配, MVP下放速度过快(峰值速度4 m/s)而造成非常明显的盐度尖峰现象。本研究结合Fofonoff(F)法、时间常数指数递归数字滤波(Giles and McDougall, GM)法和Grose提出的盐度尖峰订正方案,提出了一种新的方法,即MCT(match conductivity and temperature response time)法,通过对压力、温度和电导率传感器进行响应时间的匹配来减弱盐度尖峰。将SBE-9型CTD资料作为标准,发现订正后的资料与CTD盐度曲线的互相关系数为0.917,误差比订正前减小80%。对比35°N断面修正前后的盐度资料,订正后温盐跃层处出现的低盐区域消失。MVP的应用比常规海洋调查仪器CTD对于海洋现象的观测更有优势。
The moving vessel profiler (MVP) is a high integration and automatic equipment for marine investigation. Multi-parameter can be observed simultaneously to obtain data with high spatial resolution. Since the response time of sensors does not match between temperature and conductivity, a serious salinity spiking appears when the speed of lowering MVP is too fast (peaking speed 4 m/s). In this study, we proposed a novel method to weaken the salinity spiking via matching the response time of pressure, temperature, and conductivity sensors. The results showed that the error of corrected data was reduced by 80%compared with SBE-9 conductance temperature depth (CTD) data, and the cross-correlation with CTD data was 0.917. In addition, the area of low salinity in halocline of 35 °N section disappeared after correction. It indicated that MVP has advantages in fine structure over CTD.