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Abstract. This paper describes the University of New Hampshire Water Balance Model, WBM, a process-based gridded global hydrologic model that simulates the land surface components of the global water cycle and includes water extraction for use in agriculture and domestic sectors. The WBMwas first published in 1989; here, we describe the first fully open-sourceWBM version (v.1.0.0). Earlier descriptions of WBM methods provide the foundation for the most recent model version that is detailed here. We present an overview of themodel functionality, utility, and evaluation of simulated global riverdischarge and irrigation water use. This new version adds a novel suite ofwater source tracking modules that enable the analysis of flow-path histories on water supply. A key feature of WBM v.1.0.0 is the ability to identify the partitioning of sources for each stock or flux within the model. Three different categories of tracking are available: (1) primary inputs of water to the surface of the terrestrial hydrologic cycle (liquid precipitation, snowmelt, glacier melt, and unsustainable groundwater); (2) water that has been extracted for human use and returned to the terrestrial hydrologic system; and (3) runoff originating from user-defined spatial land units. Such component tracking provides a more fully transparent model in that users can identify the underlying mechanisms generating the simulated behavior. We find that WBM v.1.0.0 simulates global river discharge and irrigation water withdrawals well, even with default parameter settings, and for the first time, we are able to show how the simulation arrives at these fluxes by using the novel tracking functions.
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Development of the Community Water Model (CWatM v1.04) – a high-resolution hydrological model for global and regional assessment of integrated water resources management
Abstract. We develop a new large-scale hydrological and water resources model, theCommunity Water Model (CWatM), which can simulate hydrology both globallyand regionally at different resolutions from 30 arcmin to 30 arcsec atdaily time steps. CWatM is open source in the Python programming environmentand has a modular structure. It uses global, freely available data in thenetCDF4 file format for reading, storage, and production of data in acompact way. CWatM includes general surface and groundwater hydrologicalprocesses but also takes into account human activities, such as water useand reservoir regulation, by calculating water demands, water use, andreturn flows. Reservoirs and lakes are included in the model scheme. CWatMis used in the framework of the Inter-Sectoral Impact Model IntercomparisonProject (ISIMIP), which compares global model outputs. The flexible modelstructure allows for dynamic interaction with hydro-economic and water qualitymodels for the assessment and evaluation of water management options.Furthermore, the novelty of CWatM is its combination of state-of-the-arthydrological modeling, modular programming, an online user manual andautomatic source code documentation, global and regional assessments atdifferent spatial resolutions, and a potential community to add to, change,and expand the open-source project. CWatM also strives to build a communitylearning environment which is able to freely use an open-source hydrologicalmodel and flexible coupling possibilities to other sectoral models, such asenergy and agriculture.
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- Award ID(s):
- 1829999
- PAR ID:
- 10223767
- Date Published:
- Journal Name:
- Geoscientific Model Development
- Volume:
- 13
- Issue:
- 7
- ISSN:
- 1991-9603
- Page Range / eLocation ID:
- 3267 to 3298
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
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Accepted Manuscript1.0
- Journal Article:
- https://doi.org/10.5194/gmd-13-3267-2020
