A method for assessing the coastline recession due to the sea level rise by assuming stationary wind-wave climate

Abstract The method introduced in this study for future projection of coastline changes hits the vital need of communicating the potential climate change impact on the coast in the 21th century. A quantitative method called the Dynamic Equilibrium Shore Model (DESM) has been developed to hindcast historical sediment mass budgets and to reconstruct a paleo Digital Elevation Model (DEM). The forward mode of the DESM model relies on paleo-scenarios reconstructed by the DESM model assuming stationary wind-wave climate. A linear relationship between the sea level, coastline changes and sediment budget is formulated and proven by the least square regression method. In addition to its forward prediction of coastline changes, this linear relationship can also estimate the sediment budget by using the information on the coastline and relative sea level changes. Wind climate change is examined based on regional climate model data. Our projections for the end of the 21st century suggest that the wind and wave climates in the southern Baltic Sea may not change compared to present conditions and that the investigated coastline along the Pomeranian Bay may retreat from 10 to 100 m depending on the location and on the sea level rise which was assumed to be in the range of 0.12 to 0.24 m.

摘要：本研究中引入的用于海岸线变化未来预测的方法满足了传达21世纪气候变化对海岸潜在影响的关键需求。一种名为动态平衡海岸模型（DESM）的定量方法已被开发出来，用于反推历史沉积物质量收支并重建古数字高程模型（DEM）。DESM模型的正向模式依赖于由DESM模型重建的古情景，假设风浪气候稳定。海平面、海岸线变化和沉积物收支之间的线性关系通过最小二乘法回归得到构建和验证。除了对海岸线变化进行正向预测外，这种线性关系还可以利用海岸线和相对海平面变化的信息来估算沉积物收支。基于区域气候模型数据对风气候变化进行了研究。我们对21世纪末的预测表明，与当前状况相比，波罗的海南部的风浪气候可能不会改变，并且波美拉尼亚湾沿岸所研究的海岸线可能会根据位置以及假设在0.12米至0.24米范围内的海平面上升情况，后退10米至100米。