HD Model (Hydrological Discharge Model)#
Contact person
Description#
The Hydrological Discharge (HD) model calculates the lateral transport of water over the land surface to simulate discharge into the oceans. It has been validated and applied in many studies since the publication of its original global 0.5° version (Hagemann and Dümenil 1998; Hagemann and Dümenil Gates 2001). Hagemann et al. 2020 developed a high-resolution version that can be applied globally at a 5 Min. (~8-9 km) resolution. This HD version was applied and validated over Europe. The HD model has been coupled to several global and regional Earth System Models. It separates the lateral water flow into the three flow processes of overland flow, baseflow, and riverflow. Overland flow and baseflow represent the fast and slow lateral flow processes within a grid box, while riverflow represents the lateral flow between grid boxes. The HD model requires gridded fields of surface and subsurface runoff as input for overland flow and baseflow, respectively, with a temporal resolution of one day or higher.
Recent developments include:
A YAC interface has been implemented (Hagemann et al. 2023) so that HD can be used as an externally coupled model in ICON, which has been done at DWD within the ICON seemless activity.
In the CLICCS excellent cluster, the HD model has been equipped with a framework that allows the transport of desired matter compounds within the HD river network. First applications include the transport of PFOA (Simon et al., submitted), nitrogen (Hagemann et al. 2021) and phosphorus (Elizalde, pers. Comm. 2021).
The framework also includes simple parametrizations for the calculation of stream water temperature.
Model(s)#
HD Model : Apache 2.0
Programming language(s)#
FORTRAN95
Literature and Links#
Simon, P., M. Ramacher, S. Hagemann, H. Joerss, J. Bieser: POPE: a Global Gridded Emission Inventory for PFOA 1950-2020. Environmental Science & Technology, submitted.