A depth-integrated model for simulating wave-induced longshore current was developed with unstructured grids. Effects of surface roller and horizontal mixing under combined waves and currents were incorporated in the numerical model. Recommended values of model coefficients were also proposed based on sensitivity analysis. Field observations and three series of laboratory measurements including two cases conducted on the plane beach and one implemented on the ideal inlet were employed to examine the predictive capability of this model. For the field case and laboratory cases conducted on the plane beach, numerical results were compared favorably with the measured data. For the case with an ideal inlet, simulated circulation pattern is supposed to be reasonable although some deviations between numerical results and measured data still can be detected. 相似文献
全球变暖背景下的冰盖消融以及由此带来海平面上升日益明显,直接影响地球表面的陆地水质量平衡,以及固体地球瞬间弹性响应,研究冰盖质量变化的海平面指纹能够帮助深入了解未来海平面区域变化的驱动因素.本文基于海平面变化方程并考虑负荷自吸效应(SAL)与地球极移反馈的影响,借助美国德克萨斯大学空间研究中心(Center for Space Research,CSR)发布的2003年到2012年十年期间的GRACE重力场月模型数据(RL05),结合加权高斯平滑的区域核函数,反演得到格陵兰与南极地区冰盖质量变化的时空分布,并利用海平面变化方程计算得到了相对海平面的空间变化,结果表明:格陵兰与南极冰盖质量整体呈明显的消融趋势,变化速率分别为-273.31 Gt/a及-155.56 Gt/a,由此导致整个北极圈相对海平面降低,最高可达约-0.6 cm·a-1;而南极地区冰盖质量变化趋势分布不一,导致西南极近海相对海平面下降,而东南极地区近海相对海平面上升,最高可达约0.2 cm·a-1.远离质量负荷区域的全球海平面以上升趋势为主,平均全球相对海平面上升0.71 mm·a-1,部分远海地区相对海平面上升更加突出(例如北美与澳大利亚),高出全球平均海平面上升速率将近30%.此外,本文也重点探讨了GRACE监测冰盖消融结果中由于极地近海海平面变化导致的泄漏影响,经此项影响校正后的结果表明:海平面指纹效应对GRACE监测格陵兰与南极地区2003-2012期间整体冰盖消融速率的贡献分别为约3%与9%,建议在后期利用GRACE更精确地估算研究区冰盖质量变化时,应考虑海平面指纹效应的渗透影响.