On the variability of the flow along the Meso-American Barrier Reef system: a numerical model study of the influence of the Caribbean current and eddies
On the variability of the flow along the Meso-American Barrier Reef system: a numerical model study of the influence of the Caribbean current and eddies
复制标题
中美洲堡礁系统沿线水流的变化：加勒比海流和涡流影响的数值模型研究
DOI：
10.1007/s10236-005-0033-2
复制
发表时间：
2005
期刊：
影响因子：
2.3
通讯作者：
W. Heyman
中科院分区：
文献类型：
--
作者：
T. Ezer;D. Thattai;B. Kjerfve;W. Heyman
利用一个高分辨率（3-8 km网格）的西加勒比海（WCS）三维数值海洋模式，研究了沿沿着墨西哥、伯利兹、危地马拉和洪都拉斯海岸分布的中美洲堡礁系统（MBRS）附近的流场变化和强迫。中尺度变化的速度和温度沿着的珊瑚礁被发现在季节性模型模拟和观测，这些变化与曲折的加勒比电流（CC）和传播的加勒比涡。诊断计算和一个简单的同化技术相结合，以推断与特定的涡旋动态调整流。结果表明，当一个气旋涡（负海面高度异常（SSHA））被发现附近的MBRS的CC离岸移动，在洪都拉斯湾（GOH）的气旋环流加强，和一个强大的南向流动的结果沿着礁。然而，当一个反气旋涡流（正SSHA）被发现附近的珊瑚礁，CC向岸上移动，流量主要是向西穿过珊瑚礁。模型的结果有助于解释如何漂流能够传播的平均环流的方向相反时，涡旋引起的沿海环流逆转。包括中美洲泻湖西部的伯利兹礁在模型地形的影响也进行了调查，以显示准确的沿海地形在确定跨MBRS运输的变化的重要性。在穿越MBRS的运输中发现的变化（在季节和中尺度时间尺度上）可能对沿着珊瑚礁的生物活动产生重要影响，例如产卵聚集;更好地了解这些变化的性质将有助于在珊瑚礁养护和维持该区域生态系统健康方面的持续努力。
A high resolution (3–8 km grid), 3D numerical ocean model of the West Caribbean Sea (WCS) is used to investigate the variability and the forcing of flows near the Meso-American Barrier Reef System (MBRS) which runs along the coasts of Mexico, Belize, Guatemala and Honduras. Mesoscale variations in velocity and temperature along the reef were found in seasonal model simulations and in observations; these variations are associated with meandering of the Caribbean current (CC) and the propagation of Caribbean eddies. Diagnostic calculations and a simple assimilation technique are combined to infer the dynamically adjusted flow associated with particular eddies. The results demonstrate that when a cyclonic eddy (negative sea surface height anomaly (SSHA)) is found near the MBRS the CC shifts offshore, the cyclonic circulation in the Gulf of Honduras (GOH) intensifies, and a strong southward flow results along the reef. However, when an anticyclonic eddy (positive SSHA) is found near the reef, the CC moves onshore and the flow is predominantly westward across the reef. The model results help to explain how drifters are able to propagate in a direction opposite to the mean circulation when eddies cause a reversal of the coastal circulation. The effect of including the Meso-American Lagoon west of the Belize Reef in the model topography was also investigated, to show the importance of having accurate coastal topography in determining the variations of transports across the MBRS. The variations found in transports across the MBRS (on seasonal and mesoscale time scales) may have important consequences for biological activities along the reef such as spawning aggregations; better understanding the nature of these variations will help ongoing efforts in coral reef conservation and maintaining the health of the ecosystem in the region.