【作者】 仉天宇； 杜广伟； 苏奋振； 王敬贵； 陈秀法；

【Author】 ZHANG Tian yu 1,DU Guang wei 2, SU Fen zhen 1, WANG Jing gui 1,CHEN Xiu fa 1 ( 1, Institute of Geographic Sience and Resources, CAS , Beijing 100101, China; 2. Linyi Water Affairs Bureau, Linyi 276003, China)

【机构】 中国科学院地理科学与资源研究所； 临沂市兰山区水务局；

【摘要】 分析和讨论了关于网格数据梯度的定义(方向导数,梯度,最大梯度)及其应用范围,给出了解析计算公式和离散计算公式。根据海洋动力学中地转流的计算原理,讨论和分析了海洋动力网格数据梯度计算的方法,阐述了海洋网格数据梯度计算需要注意的几个基本事项。指出:在大多数情况下,应该尽可能采用基于力学原理的梯度计算方法。利用海面高度样本数据进行了梯度试算,指出利用现有软件进行计算时,需要注意不同算法之间的差别。更多还原

【Abstract】 The definitions of grid data gradient (directional derivative, gradient and maximum gradient) and their application ranges are analysed and discussed, and their analytical calculation formulas and discrete calculation formulas are given. Based on the computational theory of geostrophic current in ocean dynamics, the gradient computation methods of marine dynamic grid data are discussed and analysed, and the basical matters of gradient computation needing attention are expounded. It is concluded that the mechanics based gradient computation method shall be adopted in most cases. As a test case, the gradient computation was made by using the sea surface height sample data, and it is pointed out that the attention shall be drawn to the difference between different algorithms in making the gradient computation by using the available softwares.更多还原