Hydrological Data-Model Work in Greenland

The hydrological studies of the Greenland technical Organization in Greenland are being followed up at Copenhagen by hydrological data work as well as hydrological model-simulation. The hydrological regions vary greatly in Greenland, depending on whether the drainage basin is influenced by ablation runoff. To describe a runoff time series from these areas, a hydrological model calibration is made, followed by a simulation. In drainage basins influenced by rain and snow only, a slightly modified version of the precipitation runoff model (NAM) is applied. The parameter transfer for the determination of model input is found by intensive data analysis work here between Nuuk and Kangerluarsunnguup Tasersua (KANG) for temperature and precipitation along with detailed investigations in the basin. This is to ensure that a too short calibration period in connection with the adaption of a hydrological model to the basin data is balanced in the manner that these adapt the hydrological model, and not vice versa. In drainage basins also influenced by ablation runoff it is not possible to use a traditional precipitation runoff model but a hydrological ablation model has been developed in cooperation with The Geological Survey of Greenland. The hydrological ablation model describes the transfer of the temperature after heating and cooling factors as well as snow mobility on the ice, melting density criteria, refreezing etc. The model has been applied to the hydrological basin of Paakitsup Akuliarusersua (PAKI) at Ilulissat where 90% of the drainage basin is covered by the Ice cap. Data evaluation work prior to hydrological model calibration thus allows for a higher degree of simulation reliability.