ClimateBasis Zackenberg - Zackenberg River Hydrometric data - 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. Zackenberg River Hydrometric data:Zackenberg River Hydrometric data ClimateBasis Zackenberg:The ClimateBasis programme monitors climate and hydrology in Zackenberg, Kobbefjord and Disko (Qeqertarsuaq) and is run by Asiaq - Greenland Survey. The collected data build base-line information on climate variability and trends for all the other sub-programmes within GEM and serve as a trustworthy foundation for adaptation strategies for the Greenlandic society. The stations are embedded in Asiaq’s extensive climate and hydrology monitoring network. Furthermore, the run-off data is delivered to the World Hydrological Cycle Observing System (WHYCOS) and the Global Runoff Data Centre (GRDC) networks.

本数据集为通过基于人工流量实测建立的水位流量关系（stage-discharge relation），由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）。该水文站位于扎科恩贝格河（Zackenberg river）入峡湾处上游约2.5公里处。
2014年之后，河道水位通过传感器测量桥面至水面的垂直距离获取，并以河道内的压力传感器作为备用监测手段；2014年之前，水位则通过安装在河岸吊架上的距离传感器测量，并以水下压力传感器作为辅助支撑。
该水文站曾因积雪条件恶劣迁移过一次，且多次遭受洪水侵袭，部分年份导致站点停运，进而造成时间序列数据缺失（详细信息请参阅元数据文本文件中的时间序列说明）。流域西北部的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），此类洪水多次大幅改变河道床面形态，事后需重新建立水位流量关系。由于高水位与不断变化的河床条件，冰湖溃决洪水期间测得的流量相较于其他时段存在更大的不确定性。
扎科恩贝格河秋季封冻，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，此阶段的河道水位需针对冰体影响进行校正，以获取准确的流量计算结果；水文季首尾受冰体影响的时段，均通过基于人工流量实测得到的冰体校正因子进行修正。对于无法开展人工流量实测的年份，受冰体影响时段的数据将被排除在时间序列之外，未执行该处理的年份信息将在元数据文件中注明。如需了解本时间序列数据的相关说明，请查阅随数据附带的元数据文件。
扎科恩贝格河水文数据：本数据集隶属于ClimateBasis Zackenberg项目。该项目由Asiaq——格陵兰勘测局（Greenland Survey）运营，负责监测扎科恩贝格、科布峡湾（Kobbefjord）以及迪斯科岛（Disko，Qeqertarsuaq）地区的气候与水文状况。所收集的数据为GEM框架下所有其他子项目提供了气候变异性与趋势的基准信息，并为格陵兰社会的适应策略提供了可靠的支撑基础。该水文站纳入了Asiaq覆盖广泛的气候与水文监测网络。此外，本径流数据已提交至世界水文循环观测系统（World Hydrological Cycle Observing System, WHYCOS）与全球径流数据中心（Global Runoff Data Centre, GRDC）网络。