Estimation of extreme sea levels along the Bangladesh coast due to storm surge and sea level rise using EEMD and EVA
Estimation of extreme sea levels along the Bangladesh coast due to storm surge and sea level rise using EEMD and EVA
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DOI：
10.1002/jgrc.20310
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发表时间：
2013-09
影响因子：
--
通讯作者：
Han Soo Lee
中科院分区：
文献类型：
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作者：
Han Soo Lee
[1]基于孟加拉西部海伦点(HP)的长期海平面记录，利用集合经验模式分解(EEMD)和极值分析(EVA)对2050年风暴潮和未来海平面上升(SLR)引起的极端海平面进行了估计。EEMD是一种自适应方法，它可以对非线性趋势进行反趋势，并将潮汐运动从原始海平面记录中分离出来，从而重建高压地区的风暴潮水位。然后将重建的风暴潮水平应用于EVA，以95%的可信区间(CI)获得目标重现期的极端风暴潮。EVA获得的惠普30年、50年和100年的回报水平分别为1.59、1.66和1.75米。从EEMD获得的SLR趋势为4.46毫米/年，高于最近基于测高的1993-2007年期间3.3±0.4毫米/年的趋势。由此产生的2050年SLR估计为0.34米。因此，2050年SLR和100年风暴潮造成的极端海平面将为2.09米(95%可信区间从1.91米到2.48米)。SLR不仅取决于海水质量和体积的变化，还取决于其他因素，如局部沉降、河流流量、沉积物和植被的影响。在考虑了这些因素及其非线性后，EEMD得到的SLR的剩余非线性趋势可以看作是一个自适应海平面。
[1] Extreme sea levels due to storm surge and future sea level rise (SLR) in the year 2050 are estimated using ensemble empirical mode decomposition (EEMD) and extreme value analysis (EVA) based on long-term sea level records from Hiron Point (HP) on the coast of western Bangladesh. EEMD is an adaptive method that can detrend the nonlinear trend and separate the tidal motions from the original sea level records to reconstruct storm surge levels at HP. The reconstructed storm surge levels are then applied to EVA to obtain the extreme storm surges in the target return periods at a 95% confidence interval (CI). The 30, 50, and 100 year return levels at HP obtained by EVA are 1.59, 1.66, and 1.75 m. The SLR trend obtained from EEMD is 4.46 mm/yr over April 1990 to March 2009, which is larger than the recent altimetry-based global rate of 3.3 ± 0.4 mm/yr over the period from 1993 to 2007. The resulting SLR in 2050 is estimated as 0.34 m. Therefore, the extreme sea level in 2050 due to SLR and the storm surge at a 100 year return level would be 2.09 m (95% CI from 1.91 to 2.48 m). The SLR depends not only on changes in the mass and volume of sea water but also on other factors, such as local subsidence, river discharge, sediment and the effects of vegetation. The residual nonlinear trend of SLR obtained from EEMD can be regarded as an adaptive sea level after considering those factors and their nonlinearity.