Numerical modelling of the fall-rate behaviour of a free-fall ocean sensor and its validation

这项研究试图量化和模拟探测器重量变化对XBT(消耗性BathyThermograph)下降率的影响，XBT在过去半个世纪一直是海洋温度剖面的主要工具。在一系列直接比较的基础上，估计最常用的探头型号T-7因其探头重量变化10g而导致的落地率变化约为1%。这几乎等于相对权重变化。当它应用于制造商的质量控制中的重量公差时，重量变化对下落率的影响被合理地限制，并且本研究的结果给出了XBT下落率偏差的一些上限，这在过去十年中一直是关于改进历史海洋温度数据档案的争论的问题。

This study attempted to quantify and model the impact of variance in probe weight on the fall-rate of XBT (expendable bathythermograph), which has been a major tool for ocean temperature profiling over the last half a century. Based on a series of direct comparisons, the change of fall-rate of T-7, the most popularly-used probe type, caused by a change of 10g in its probe weight is estimated to be about 1%. This is almost equal to the relative weight change. When this is applied to the manufacturers' weight tolerance in their QC, the influence of weight change on the fall-rate is reasonably confined, and the results of this study give some upper limit on the XBT fall-rate bias, which has been a matter of debate over the last decade for the improvement of the historical ocean temperature data archive.