Skallingen is a dune-capped, barrier spit fronting the Danish Wadden Sea inrnwestern Jutland (55° 30’ N 8° 20’ E), which experiences a semi-diurnal, small meso-tidalrnregime. Extreme levels, which historically have reached +4.40 m DNN (Danish OrdnancernDatum), amplify the astronomic tides; such levels are induced by storm surges in thernsouthern North Sea. The upper shoreface slopes at ? 0.008, to provide a wide intertidalrnzone characterized by two or three, quasi-permanent, nearshore bars and ephemeral swashrnbars. Moderate-to-high wave energies in association with surges cause significantrnadjustments to the foreshore. The innermost swash bar is often eliminated completely andrnsediment exchanged between the upper and lower foreshore to produce a near-planar beachrnat a significantly lower slope. At such times the dunes are susceptible to severe erosion andrnrecession. Annual shoreline recession rate is ~7.4 m a-1, but recession of ~44 m may occurrnin a single surge (1990). Sediment exchange across the supra-tidal, inter-tidal and sub-tidalrnzones of this sandy barrier system has been the focus of a multi-year study on thernMorphodynamics of Storm-Surge Shorelines (MOSS).rnOn October 30, 2000, a surge of 3.02 m was recorded in the lagoon behind the barrier atrnEsbjerg Harbour. On the foreshore, the surge raised water levels to the base of the dunernramp, which was eroded completely and the foredune was cliffed. The water level wasrnrelatively short-lived but at the peak of the surge, overwash of the barrier occurred in arnnumber of locations. The surge was characterized by steep gradients in the mean waterrnsurface elevation across the intertidal zone, generating strong offshore currents up to 0.56rnm s1; longshore currents up to 0.80 m s1 were also recorded. Sediment transport wasrndominated by these mean flows, even though large low frequency oscillations were present.rnThere was a net gain of sediment in the intertidal zone (~12 m3 per metre width of beach),rnas a result of erosion of the upper foreshore and accretion in the lower foreshore. The prsurgernswash bar was eliminated and the deep trough associated with the first nearshore barrnwas infilled. The dominantly 3-dimensional, morpho-circulation system which had existedrnprior to the storm was changed to a simpler 2-dimensional system.
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机译：Skallingen是沙丘覆盖的障碍物，位于日德兰半岛西北部（55°30′N 8°20′E）的丹麦瓦登海前，经历半日小中潮汐时期。历史上已经达到了+4.40 m DNN（丹麦军械基准）的极端水平，放大了天文潮。这种水平是由北南北海的风暴潮引起的。上岸面坡度为？ 0.008，以提供一个潮间带宽的区域，其特征是两个或三个准永久性近岸钢筋和临时偏斜钢筋。与浪涌相关的中到高波能量会导致对前岸的重大调整。通常，最里面的旋转斜杠通常被完全消除，并且在上，下前滨之间交换了沉积物，从而以明显较低的坡度产生了近平面的滩涂。在这种时候，沙丘容易受到严重侵蚀和衰退。年海岸线衰退率约为7.4 m a-1，但一次浪涌可能会发生约44 m的衰退（1990年）。跨沙质屏障系统的潮间，潮间和潮间带的泥沙交换一直是对风暴潮岸线（MOSS）地貌动力学的多年研究的重点。2000年10月30日，在屏障埃斯比约港后面的泻湖中记录到3.02 m。在前岸，浪涌使水位上升至dunernramp的底部，该底部被完全侵蚀，而前额被倾斜。水位相对来说是短暂的，但是在浪涌的高峰期，在很多地方都发生了障碍物的过冲。潮汐的特征是潮间带平均水面高度的陡峭梯度，产生了高达0.56rnm s1的强海流。还记录了高达0.80 m s1的近岸洋流。即使存在较大的低频振荡，这些平均流量仍控制着泥沙运移。rn潮间带有净沉积物（每米海滩宽度约12 m3），是前滨上游侵蚀和积聚的结果在较低的前滨。取消了prsurgernswash条，并填充了与第一个近岸barrn相关的深槽。在暴风雨之前就已经存在的占主导地位的3维形态循环系统被改为一个较简单的2维系统。
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