Pressure and processed water levels from the Time Series Station Spiekeroog, 2005-2011

The quality of water level time series data strongly varies with periods of high and low quality sensor data. In this paper we are presenting the processing steps which were used to generate high quality water level data from water pressure measured at the Time Series Station (TSS) Spiekeroog. The TSS is positioned in a tidal inlet between the islands of Spiekeroog and Langeoog in the East Frisian Wadden Sea (southern North Sea). The processing steps will cover sensor drift, outlier identification, interpolation of data gaps and quality control. A central step is the removal of outliers. For this process an absolute threshold of 0.25m/10min was selected which still keeps the water level increase and decrease during extreme events as shown during the quality control process. A second important feature of data processing is the interpolation of gappy data which is accomplished with a high certainty of generating trustworthy data. Applying these methods a 10 years dataset (December 2002-December 2012) of water level information at the TSS was processed resulting in a seven year time series (2005-2011).

水位时序数据的质量随传感器数据的高低质量时段显著波动。本文详述了从施皮克奥格（Spiekeroog）时序站（Time Series Station, TSS）测得的水压数据中生成高质量水位数据的处理流程。该时序站位于东弗里西亚瓦登海（北海南部）施皮克奥格岛与朗格奥格岛之间的潮汐水道中。本处理流程涵盖传感器漂移校正、异常值识别、数据间隙插值与质量控制环节。核心步骤为异常值剔除：本次处理选用0.25米/10分钟的绝对阈值，经质量控制验证，该阈值可完整保留极端事件期间的水位升降过程。数据处理的另一关键环节为间隙数据插值，该方法可高置信度生成可靠数据。通过上述方法，研究人员对该时序站2002年12月至2012年12月的10年水位数据集进行处理，最终得到2005年至2011年的7年时序数据集。