基于SCHISM模式的全球潮波模拟

Global tide simulation based on the semi-implicit cross-scale hydroscience integrated system model

基于非结构网格半隐式跨尺度海洋模式(semi-implicit cross-scale hydroscience integrated system model,SCHISM),作者采用非结构三角网格,对全球大洋潮波进行数值模拟。通过调和分析,将196个潮位站的实测数据与模拟结果进行比较验证,两者符合良好,M_(2)、K_(1)分潮同潮图的形态也与TPXO8、FES_(2)014b和NAO.99b模型给出的相似。根据模拟结果,给出了M_(2)、S_(2)、K_(1)、O14个主要分潮的同潮图。结果表明,太平洋中存在8个M_(2)分潮无潮点,大西洋中存在4个M_(2)分潮无潮点,印度洋中存在3个M_(2)分潮无潮点。总体上来说,M_(2)分潮在北太平洋和北大西洋东岸附近海域的振幅大于西岸附近海域的振幅,而在南太平洋和南大西洋情况相反。S_(2)分潮分布特征与M_(2)分潮类似,但振幅较小。太平洋中存在5个K_(1)分潮无潮点,大西洋中存在3个K_(1)分潮无潮点,印度洋中存在2个K_(1)分潮无潮点。K_(1)分潮的振幅普遍较小,在大部分海域不超过30 cm,在北太平洋和南极洲附近海域,由大洋向近岸有增加的趋势。太平洋中存在4个O1分潮无潮点,大西洋和印度洋中各存在2个无潮点。O1分潮在大部分海域不超过20 cm,在北太平洋和南极洲附近海域,由大洋向近岸有增加的趋势。最后,讨论了本模型与对比模型之间误差存在的原因。

Based on the SCHISM(semi-implicit cross-scale hydroscience integrated system model),an unstructured triangular grid is used to numerically simulate global ocean tides.Through harmonic analysis,the measured data of 196 tidal stations are compared with simulated results to verify that the two are in good agreement.The shape of the cotidal global M_(2) and K_(1) chart components were found to be similar to those given by the TPXO8,FES_(2)014b,and NAO99.b models.According to the simulated results,the cotidal charts of the four main components of M_(2),S_(2),K_(1),and O1 are given.The results show that there are eight M_(2) amphidromic points in the Pacific Ocean,four M_(2) am-phidromic points in the Atlantic Ocean,and 3 M_(2) amphidromic points in the Indian Ocean.Generally speaking,the amplitudes of the M_(2) tidal component in the waters near the eastern border of the North Pacific and North Atlantic oceans are always greater than that of the waters near the western border,whereas the opposite is true in the South Pacific and South Atlantic oceans.The distribution characteristics of the S_(2) tidal component are similar to that of the M_(2) tidal component,although the amplitude is smaller.There are five K_(1) amphidromic points in the Pacific Ocean,three K_(1) amphidromic points in the Atlantic Ocean,and two K_(1) amphidromic points in the Indian Ocean.The amplitude of the K_(1) tidal component is generally small,not exceeding 30 cm in most sea areas,in the waters near the North Pacific and Antarctica with an increasing trend from an ocean to a nearshore.There are four am-phidromic points of O1 in the Pacific Ocean and two amphidromic points in the Atlantic and Indian Oceans.The amplitude of the O1 tidal component does not exceed 20 cm in most sea areas,and in the waters near the North Pa-cific and Antarctica there is an increasing trend from an ocean to a nearshore.Finally,the reasons for the errors between the proposed model and the comparison model are discussed.