基于拉格朗日方法的南海自动剖面浮标轨迹模拟系统*

南海自动剖面浮标轨迹模拟系统包括高分辨率模式流场、拉格朗日追踪模型和垂向浮标运动参数化方案等三个核心部分。该系统可在南海范围内模拟两类自动剖面浮标: 传统自动剖面浮标(停滞深度为1000m, 最大下潜深度为2000m)和新型深海自动剖面浮标(停滞深度为距海底500m)。通过对南海现有的6个传统浮标的模拟, 该系统可以预测其100d内的漂流轨迹。通过与真实浮标轨迹数据的对比, 验证了该模拟系统的准确性。此外, 根据该系统, 我们初步探讨了深海自动剖面浮标阵列(时空分辨率为2°×2°×30d)在南海内区布放方案的可行性。该模拟系统的建立和完善将有助于对现有传统剖面浮标布放策略进行优化, 并对未来深海剖面浮标在南海的推广应用提供初步的理论依据。

An Argo trajectory simulation system for the South China Sea using Lagrangian method*

Our Argo trajectory simulation system for the South China Sea (SCS) contains the high-resolution ambient velocity field, a Lagrangian particle tracking model and the parameterization that represents the vertical motions of profiling Argo floats. This system is applied to simulate both conventional Argo floats (typically parked at 1000 m depth and profiling to 2000 m depth) and Deep Argo floats (parked at 500 m above the seafloor) within the SCS. By conducting the simulation with the counterparts of six core Argo floats serviced in the SCS, we find the displacements of synthetic floats from the simulation system resemble the real float displacements over 100-day time intervals. We therefore judge the simulations for core Argo are robust and further apply the system to simulate a potential Deep Argo array (with the resolution of 2°×2°×30 day). The results explore both the representativeness and the predictability of float displacements, which may provide a basis to understand float displacements in the deep layer as well as to contribute to planning deep Argo array program.