Latest news in the HYPE code

New model capabilities

During the last year, HYPE has implemented a new isotope routine to accurately simulate stable isotopes of water (O18 and H2). To this end, we integrated the isoWATFLOOD model (Stadnyk-Falcone, 2008) into HYPE. This work is part of the ISOSCAN project and was done in collaboration with Prof. Dr. Tricia Stadnyk from the University of Calgary (Canada). HYPE has now new process formulations for isotope fractionation and the splitting between evaporation and transpiration. To run the model, isotope forcing data are required.

In addition, a new model for simulating recharge and discharge areas within a catchment was introduced. This is the first time HYPE has a lateral flow between classes within a subbasin. With this new feature, some classes are chosen to represent recharge areas, while other classes represent discharge areas. A part of the (originally calculated) runoff from the recharge classes is redirected to the discharge classes where it is spread equally over their area and increases the groundwater level and runoff from those classes.

Model improvements

During the past months, several improvements have been made for simulations with sub-daily timesteps. More processes now work also for sub-daily time steps, most notably the optional PET models. The new tutorial for sub-daily timesteps Tutorial sub-daily time steps in HYPE [HYPE Model Documentation] has tables that list the adapted processes. The growth start model was adapted to sub-daily time steps as it was improved for use in changing climate with a temperature-dependent alternative. The optional snowfall distribution models redistributes the snowfall of a catchment among the classes within a subbasin, or between subbasins, depending on wind. Another new feature distributes snowfall to all downwind subbasins within a distance range depending on wind speed. We have also introduced an option to reset the snow pack once per year.

Infrastructure changes

Observations for classgroups have been introduced with separate observations files. The new observation files can hold observations of different HYPE variable IDs, but one classgroup each. To facilitate better housekeeping, the users can specify their own metadata. These are given in info.txt, and transferred to HYPE output files. The possibility to have timeseries of monthly values of soil leakage- and load input data was added to facilitate more time-dependent input data to HYPE. The work on this is ongoing. 

HYPE tools

The HYPEtools R package provides a toolbox of functions to support HYPE modelers with creating and modifying model files and analyzing and visualizing model results. Features of the package include streamlined file import and export, standard evaluation plot routines, interactive mapping, and diverse post-processing and aggregation routines for hydrological model analysis. In 2024, scaling functions (i.e. ScalePar, ScaleAquiferData, and ScaleFloodData) were added to HYPEtools in order to help users convert HYPE models from daily time steps to other time steps (e.g. hourly). A HYPEtools reference paper was also published in 2024.