Discharge at a cross section of the river, (m3/s)

River discharge measured with continuous water level measurements converted by a stage-discharge relation based on manual discharge measurements. 15 min sample values in m3/s. The hydrometric station is located ~2.5 km upstream of where the Zackenberg river enters the fjord. After 2014, water level in the river is measured by sensors logging the vertical distance from the bridge down to the water surface, backed up by pressure sensors in the river. The time series starts in 1996. Before 2014, water level was measured by a distance sensor mounted on a gallows rack on the river bank, supported by pressure sensors in the water. The station was moved once because of bad snow conditions, and was also exposed to floods, in some years this resulted in downtimes for the station and subsequent gaps in the timeseries (see timeseries comments in the metadata text file for details). Nearly every year, a glacier lake outburst flood (GLOF) is released from the A.P. Olsen glacier which lies in the northwestern corner of the river catchment. Several of these GLOFs have modified the river bed to a large degree, and a new stage-discharge relation has had to be established afterwards. The discharge measured during the GLOF period is subject to larger uncertainties than other periods due to high water levels and changing bed conditions. Zackenberg river freezes in Autumn and has no flow through winter, except in rare years when the GLOF happens during the winter months. The spring flow runs on top of the winter ice until the channel has melted down to the river bed, and the river stage in this period needs to be corrected for the influence of the ice in order to calculate correct discharge. Ice affected periods at both the start and the end of the season are corrected for by ice correction factors based on manual discharge measurements. For years when manual discharge measurements could not be made, data for the ice-affected periods are excluded from the time series. Years where this has not been done are given in the metadata. Please read the metadata file provided with the data for comments related to the data in this timeseries.本数据集为基于人工流量实测所建立的水位-流量关系（stage-discharge relation），将连续水位观测数据转换得到的河道流量数据，采样间隔为15分钟，单位为立方米每秒（m³/s）。该水文站位于扎科本河（Zackenberg river）入峡湾处上游约2.5公里处。2014年后，河道水位通过传感器测量桥面至水面的垂直距离获取，并以河内置压力传感器作为备份监测手段；2014年前，水位监测由安装在河岸吊架支架上的距离传感器完成，辅以水中压力传感器提供辅助监测。该水文站曾因积雪条件恶劣搬迁过一次，且曾多次遭遇洪水侵袭，部分年份导致站点停运，进而造成时间序列数据出现缺失，详细情况请参阅元数据（metadata）文本文件中的时序注释。扎科本河流域西北角的A.P.奥尔森冰川（A.P. Olsen glacier）几乎每年都会引发冰湖溃决洪水（glacier lake outburst flood, GLOF），此类冰湖溃决洪水多次大幅改变了河床形态，因此后续需重新建立水位-流量关系。由于高水位与河床条件持续变化，冰湖溃决洪水期间测得的流量相较于其他时段具有更高的不确定性。扎科本河于秋季封冻，冬季无径流，仅在极少数冬季发生冰湖溃决洪水的年份例外。春季径流会在冬季冰层之上流动，直至河道完全消融至河床，此阶段的河流水位需校正冰层影响以获取准确的流量计算结果。每年水文季始末受冰层影响的时段，均通过基于人工流量实测建立的冰层校正因子完成校正。对于无法开展人工流量实测的年份，受冰层影响时段的数据将被从时间序列数据集中剔除；未执行该剔除操作的年份已在元数据中注明。请参阅数据集附带的元数据文件，以获取本时间序列数据集相关的补充说明。