Data Repository Sand Banks SW North Sea

Sand banks in the SW North Sea are heavily influenced by the relationship between the critical shear stress of the sediment and the shear stress induced by the water motions. The data shows how the sand bank distribution is bounded to certain shear stress conditions. It appears that the ratio between the maximum bed shear stress and the critical shear stress of the surface sediments (simply referred to as shear stress ratio) has to exceed a threshold of nine to launch sand bank formation to a greater extend. Previous prediction models have suggested that sand banks form when the shear stress of the water motions exceeds the critical shear stress of the sediment. Subsequently, these findings can improve further predictions of sand bank formation. The dataset contains: - Shear stress ratio as a tif-raster file The shear force ratio was calculated using several raster datasets provided by the Helmholtz Centre of Geesthacht. - Current induced shear stress / critical shear stress - ratio Again, values were calculated using datasets from the Helmholtz Centre of Geesthacht. - Sand bank shapefile

北海西南部海域的沙坝（sand banks），其发育过程显著受沉积物临界剪切应力（critical shear stress）与水流运动诱导剪切应力之间的相互关系影响。本数据集揭示了沙坝分布受特定剪切应力条件约束的规律。研究发现，床面最大剪切应力（bed shear stress）与表层沉积物临界剪切应力的比值（简称为剪切应力比（shear stress ratio））需超过9这一阈值，方能在更大程度上启动沙坝形成过程。此前的预测模型曾提出，当水流运动产生的剪切应力超过沉积物临界剪切应力时，沙坝便会形成。上述研究发现可进一步优化沙坝形成的预测工作。本数据集包含以下内容：
- 剪切应力比TIFF栅格文件（tif-raster file）：该剪切力比值基于赫尔姆霍茨基尔斯特赫特中心（Helmholtz Centre of Geesthacht）提供的多份栅格数据集计算所得。
- 水流诱导剪切应力与临界剪切应力的比值：该数值同样通过赫尔姆霍茨基尔斯特赫特中心提供的数据集计算得到。
- 沙坝形状文件（Shapefile）