一种提高深远海全深度声速剖面重构精度的方法

开展多波束水深测量应同步进行声速剖面探测。因海上作业条件恶劣、作业时间受限及设备性能局限等影响,在深远海海域常获取不到全深度的实测声速剖面。尽管利用温盐场模型可将声速剖面直接延拓至实地水深的最大深度,但这种气候态平均声速剖面与实际的声速剖面间存在不可控的系统性偏差,会给声速改正及水深测量成果带来质量隐患。给出了一种提高深远海全深度声速剖面重构精度的方法,即利用有效探测深度附近的实测温度盐度值,对大于有效探测深度的各水层的模型温度盐度值施加程度不一的约束控制。结果表明,经优化后全深度声速剖面的重构精度得到明显提高,其中2个XCTD站点声速剖面的互差SSPD分别由-2.5～1.0 m/s优化为0.0～1.0 m/s、0.0～2.6 m/s优化为-1.5～0.0 m/s; 2个CTD站点声速剖面的互差SSPD分别由-0.5～1.7 m/s优化为-0.4～0.3 m/s、-2.15～0.8 m/s优化为-1.4～0.8 m/s。

A method to improve the reconstruction accuracy of the full-depth sound speed profile in deep sea water

Detection of sound speed profile should be carried out simultaneously in multibeam sounding.It is difficult to obtain full-depth sound speed profile due to the influence of offshore operation conditions in deep sea water.Although the models of temperature and salinity can be used to extend the sound speed profile directly to the maximum depth of the in-situ water depth,there is an uncontrollable systematic deviation between the average sound speed profile of the climate state and the actual sound speed profile,which bring some quality question to the result of sound speed correction and water depth measurements.In this paper,a method is proposed to improve the reconstruction accuracy of the full-depth sound speed profile in the deep sea water.In other words,the measurements of the temperature and salinity near the effective detection depth are used to control the model temperature and salinity values of each water layer larger than the effective detection depth.The results show that the reconstruction accuracy of the full-depth sound speed profile is significantly improved after optimization.The difference of sound speed profile of two XCTD sites are optimized from-2.5~1.0m/s to 0.0~1.0m/s,0.0~2.6m/s to-1.5~0.0m/s,respectively.The difference of sound speed profile of two CTD sites are optimized from-0.5~1.7m/s to-0.4~0.3m/s,-2.15~0.8m/s to-1.4~0.8m/s,respectively.