PCR-GLOBWB 2: a 5 arcmin global hydrological and water resources model

Abstract

Abstract. We present PCR-GLOBWB 2, a global hydrology and water resources model. Compared to previous versions of PCR-GLOBWB, this version fully integrates water use. Sector-specific water demand, groundwater and surface water withdrawal, water consumption, and return flows are dynamically calculated at every time step and interact directly with the simulated hydrology. PCR-GLOBWB 2 has been fully rewritten in Python and PCRaster Python and has a modular structure, allowing easier replacement, maintenance, and development of model components. PCR-GLOBWB 2 has been implemented at 5 arcmin resolution, but a version parameterized at 30 arcmin resolution is also available. Both versions are available as open-source codes on https://github.com/UU-Hydro/PCR-GLOBWB_model (Sutanudjaja et al., 2017a). PCR-GLOBWB 2 has its own routines for groundwater dynamics and surface water routing. These relatively simple routines can alternatively be replaced by dynamically coupling PCR-GLOBWB 2 to a global two-layer groundwater model and 1-D–2-D hydrodynamic models. Here, we describe the main components of the model, compare results of the 30 and 5 arcmin versions, and evaluate their model performance using Global Runoff Data Centre discharge data. Results show that model performance of the 5 arcmin version is notably better than that of the 30 arcmin version. Furthermore, we compare simulated time series of total water storage (TWS) of the 5 arcmin model with those observed with GRACE, showing similar negative trends in areas of prevalent groundwater depletion. Also, we find that simulated total water withdrawal matches reasonably well with reported water withdrawal from AQUASTAT, while water withdrawal by source and sector provide mixed results.

Added Value of Large Ensemble Simulations for Assessing Extreme River Discharge in a 2 °C Warmer World

“…Although the hydrological model has been extensively validated and shows good agreement with observational records (Sutanudjaja et al, 2018), there is insufficient observational data to evaluate the performance of PCR-GLOBWB for extreme floods and droughts. This is fundamentally different from observational records (which are subject to changing management conditions and transient climate) and transient model simulations.…”

“…Terrestrial hydrology was simulated using the GHM PCR-GLOBWB 2 (Sutanudjaja et al, 2018). PCR-GLOBWB computes a water balance at a 0.5 • grid scale, forced by daily precipitation, 2-m air temperature, and potential evapotranspiration from EC-Earth.…”

“…PCR-GLOBWB computes a water balance at a 0.5 • grid scale, forced by daily precipitation, 2-m air temperature, and potential evapotranspiration from EC-Earth. Full details are provided in Sutanudjaja et al (2018). PCR-GLOBWB includes modules to simulate land surface processes, groundwater, irrigation, domestic and industrial water use, and river routing including lakes and man-made reservoirs.…”

High‐Resolution Global Water Temperature Modeling

“…A lack of detailed global observations does not allow the model to constrain these operations in a realistic fashion. Reservoir operations in the current version of the model are optimized for hydropower, and similar to the reservoir operations currently implemented in PCR‐GLOBWB 2 (Sutanudjaja et al, ). In general the reservoir storage is kept between 30% and 70% of the full capacity and the outflow is scaled proportionally to the annual average discharge.…”

Global GRACE Data Assimilation for Groundwater and Drought Monitoring: Advances and Challenges

“…This set of specific yield values is provided in Table S2 (see the supporting information). Due to the lack of aquifer geological information for wells located in Uganda, Europe, and Australia, specific yield estimates were taken from the 0.5° global data set used by the PCRaster Global Water Balance (PCR‐GLOBWB) model (Sutanudjaja et al, ). Note that CLSM simulates water storage changes directly and, thus, does not need specific yield as an input parameter.…”