surface gravity wave meaning in English

表面重力波
地表重力波

Though adopting the - coordinate transformation in the control equations and mode - splitting technique , the external mode ( surface gravity waves ) is solved by the improved double - sweep - implicit finite difference method ; the internal mode ( internal gravity waves ) untilizes the eulerian - lagrangian method , which improves the implicit - difference scheme for the vertical direction . the newly developed 3d numerical tidal model with implicit scheme has been successfully applied in the radial sandbanks area
基于过程分裂法及垂向坐标伸缩变换，外模式采用改进型双步全隐有限差分dsi法，内模式采用欧拉?拉格朗日公式，改进了三维垂向隐式格式，成功地建立了南黄海辐射状沙脊群海域三维全隐格式潮流数学模型。