ABSTRACT

The ability to provide rapid decision support and more precise search area coordinates for rescuers to conduct search and rescue operations at sea are of high impact value for marine and maritime stakeholders. Search and rescue operations rely on accurate information about metocean conditions to locate objects in the ocean. These include local knowledge, operational ocean and wind forecasts and empirical drift relationships between ocean currents, ocean surface winds and the objects being searched for. To provide more accurate decision support for rescuers looking for persons or objects lost at sea, a virtual particle tracking tool was combined with an empirical Leeway drift model. The Lagrangian Ocean Search Targets (LOST) application builds on a Lagrangian ocean analysis framework which has been adapted to provide real-time estimates of the positions of objects based on operational ocean and wind forecasts. LOST incorporates the impact of ocean currents, surface winds and stochastic motion, the latter being critical in accounting for sub-grid scale processes that are not resolved in the ocean and wind forecasts. This study assesses the accuracy of LOST, demonstrating its feasibility as a decision support tool for search and rescue operations by applying it to three use cases in the South African regional ocean. These use cases are real-life scenarios that highlight the value of combining state-of-the-art ocean and wind forecasting systems with Lagrangian ocean analyses frameworks and sub-grid scale parameterisation to support global operational oceanography.

摘要

为救援人员在海上进行搜救行动提供快速决策支持和更精确的搜索区域坐标的能力对于海洋和海事利益相关者具有很高的影响价值。搜索和救援行动依靠有关海洋气象条件的准确信息来定位海洋中的物体。其中包括当地知识、可操作的海洋和风力预报以及洋流、海面风和正在搜索的目标之间的经验漂移关系。为了为寻找海上失踪人员或物体的救援人员提供更准确的决策支持，将虚拟粒子跟踪工具与经验 Leeway 漂移模型相结合。Lagrangian Ocean Search Targets (LOST) 应用程序建立在 Lagrangian 海洋分析框架之上，该框架已经过调整，可根据海洋和风力预报提供实时物体位置估计。LOST 结合了洋流、表面风和随机运动的影响，后者对于解释海洋和风预报中未解决的亚网格尺度过程至关重要。本研究评估了 LOST 的准确性，通过将其应用于南非区域海洋的三个用例，证明了其作为搜索和救援行动决策支持工具的可行性。