Dispersion and connectivity estimates along the U.S. west coast from a realistic numerical model
Dispersion and connectivity estimates along the U.S. west coast from a realistic numerical model
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根据现实数值模型对美国西海岸的分散和连通性进行估计
DOI：
10.1357/002224011798147615
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发表时间：
2011
影响因子：
0.5
通讯作者：
J. Barth
中科院分区：
文献类型：
--
作者：
Patrick T. Drake;C. Edwards;J. Barth
近表面颗粒扩散，幼虫扩散和连接沿着美国西海岸进行了探索，使用一个现实的数值模型的加州电流系统。季节性模型的速度进行了定性和定量评价使用全球漂流计划的数据。该模型显示了一个明确的季节性周期的涡旋能量在海岸附近的能量最大西南的主要岬。涡流速度与漂移的估计在夏季和秋季的空间比较。在加州和俄勒冈州海岸10公里内的水柱上部20米处释放了超过600万个被动拉格朗日粒子，并跟踪了7年。亚网格尺度的垂直湍流的影响是参数化的随机行走模型。由此产生的轨迹产生的粒子扩散的气候图。颗粒密度随释放区域、释放季节和释放后时间而变化。扩散距离和沿海连接不同的季节释放，释放位置，释放深度和远洋幼虫持续时间（PLD）。连通性显然受到法拉隆湾和门多西诺角等主要地理特征的影响。在中度（30-60天）的PLD下，平均扩散距离为10-230公里，标准差为130-220公里。从帕洛斯弗迪斯点苏尔的释放位置，分散的主要方向是向北的一个温和的PLD，无论季节。对于长PLD（120-180天），平均扩散距离较大（~40-440 km），标准差为~330540 km。在冬季，由于长PLD，扩散主要是向南的释放地点以北的角竞技场。增加释放深度到40-60米改变了50-250公里的平均扩散距离极地，但对标准偏差的影响不大。点概念并没有作为一个障碍，分散在南加州湾的来源地区。
Near-surface particle dispersion, larval dispersal and connectivity along the U.S west coast were explored using a realistic numerical model of the California Current System. Seasonal model velocities were qualitatively and quantitatively evaluated using Global Drifter Program data. The model displayed a clear seasonal cycle of eddy energy near the coast with energy maxima southwest of major headlands. Eddy speeds were correlated with drifter-based estimates during summer and fall when compared spatially. Over six million passive, Lagrangian particles were released in the upper 20 m of the water column within 10 km of the California and Oregon coasts and tracked for 7 years. The effect of subgridscale vertical turbulence was parameterized with a random walk model. Resulting trajectories yielded climatological maps of particle dispersion. Particle densities varied with release region, release season and time-since-release. Dispersal distances and coastal connectivity varied with season of release, release location, release depth and pelagic larval duration (PLD). Connectivity was clearly influenced by major geographic features such as the Gulf of the Farallones and Cape Mendocino. Given a moderate (30-60 day) PLD, mean dispersal distances varied from ~10-230 km, with standard deviations of ~130-220 km. For release locations from Palos Verdes to Point Sur, the primary direction of dispersal was northward for a moderate PLD, regardless of season. For long PLDs (120-180 day), mean dispersal distances were larger (~40-440 km), with standard deviations of ~330540 km. In winter given a long PLD, dispersal was primarily southward for release locations north of Point Arena. Increasing release depths to 40-60 m altered mean dispersal distances by 50-250 km polewards, but had little effect on standard deviations. Point Conception did not act as a barrier to dispersal for source regions in the Southern California Bight.