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Comprehensive assessments of hydrological components are crucial for enhancing operational water supply simulations. However, hydrological models are often evaluated based on their surface flow simulations, while the validation of subsurface and groundwater components tends to be overlooked or not well documented. In this study, we evaluated the outputs of two hydrological models, the Large Basin Runoff Model (LBRM) and the Weather Research and Forecasting – Hydrological modeling extension package (WRF-Hydro), for potential implementation in operational water balance forecasting in the Great Lakes region. We examined the simulated hydrological variables including surface (e.g. snow water equivalent, evapotranspiration, and streamflow), subsurface (e.g. soil moisture at different layers), and groundwater components with observed or reference data from ground-based stations and remotely sensed images. The findings of this study provide valuable insights into the capabilities and limitations of each model. These findings contribute to more informed water management strategies for the Great Lakes region.
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DRYP 1.0: a parsimonious hydrological model of DRYland Partitioning of the water balance
Abstract. Dryland regions are characterised by water scarcity and are facingmajor challenges under climate change. One difficulty is anticipating howrainfall will be partitioned into evaporative losses, groundwater, soilmoisture, and runoff (the water balance) in the future, which has importantimplications for water resources and dryland ecosystems. However, in orderto effectively estimate the water balance, hydrological models in drylandsneed to capture the key processes at the appropriate spatio-temporal scales.These include spatially restricted and temporally brief rainfall, highevaporation rates, transmission losses, and focused groundwater recharge.Lack of available input and evaluation data and the high computational costsof explicit representation of ephemeral surface–groundwater interactionsrestrict the usefulness of most hydrological models in these environments.Therefore, here we have developed a parsimonious distributed hydrologicalmodel for DRYland Partitioning (DRYP). The DRYP model incorporates the keyprocesses of water partitioning in dryland regions with limited datarequirements, and we tested it in the data-rich Walnut Gulch ExperimentalWatershed against measurements of streamflow, soil moisture, andevapotranspiration. Overall, DRYP showed skill in quantifying the maincomponents of the dryland water balance including monthly observations ofstreamflow (Nash–Sutcliffe efficiency, NSE, ∼ 0.7),evapotranspiration (NSE > 0.6), and soil moisture (NSE ∼ 0.7). The model showed that evapotranspiration consumes > 90 % of the total precipitation input to the catchment andthat < 1 % leaves the catchment as streamflow. Greater than 90 % of the overland flow generated in the catchment is lost throughephemeral channels as transmission losses. However, only ∼ 35 % of the total transmission losses percolate to the groundwater aquiferas focused groundwater recharge, whereas the rest is lost to the atmosphereas riparian evapotranspiration. Overall, DRYP is a modular, versatile, andparsimonious Python-based model which can be used to anticipate and plan forclimatic and anthropogenic changes to water fluxes and storage in drylandregions.
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- Award ID(s):
- 1700555
- PAR ID:
- 10384497
- Date Published:
- Journal Name:
- Geoscientific Model Development
- Volume:
- 14
- Issue:
- 11
- ISSN:
- 1991-9603
- Page Range / eLocation ID:
- 6893 to 6917
- 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-14-6893-2021
