Mary Michael uses physically-based numerical modeling to simulate hydrologic processes and connections to the land surface and lower atmosphere. Her research includes running the hydrologic model ParFlow, coupled to land surface and meteorological models in highly parallelized computing environments, to study how land disturbance and groundwater storage anomalies impact the surface turbulent fluxes and convective boundary layer. Understanding groundwater-land-atmosphere dynamics is an important step to improving hydrologic representation in weather and climate models and predicting future water resources under a changing climate.
Rachel is studying ways to better represent the subsurface in the CONUS model, and addressing several questions: preserving heterogeneity in continental-scale products of hydraulic conductivity (K); the relationship between K and water table distribution in integrated models; using watershed morphology to infer K; differences in available continental-scale subsurface products; the effect of model depth on the water table.
The East River catchment is a representative headwater basin of the Colorado River, which in turn supplies the Southwest United States with water for energy, irrigation, and municipal use. Given that 85% of streamflow is generated in small, topographically-complex basins, more research is needed to understand nutrient and water cycling in these regions. Anna’s research in the East River focuses on better predicting water availability in these regions through improving snow models using sensitivity analysis as well as through model development of energy flux representation using a comparison of model simulations to field observations.
Lauren’s research combines integrated hydrologic modeling and remote sensing to evaluate and constrain groundwater depletion in the San Joaquin River Basin, a critical portion of California’s Central Valley. Using a fully integrated hydrologic model we can evaluate how water management activities, including groundwater extraction and irrigation, and climate variability, such as the recent historic drought, impact groundwater and surface water storage and interactions. Through the course of her PhD, Lauren will use this model to explore the vulnerabilities of various components of the food-energy-water nexus, including agricultural production, hydropower, and environmental demands; and evaluate how natural variability and changes in climate may impact the delicate balance between these systems.
Land cover, subsurface, and topographic heterogeneity have all been shown to control infiltration rates, subsurface flow, soil moisture, plant water use, and energy flux distributions (Maxwell, 2010; Atchley and Maxwell, 2011). Although other models have focused on issues of scaling and resolution over large areas, some questions remain regarding the effects of small-scale heterogeneity. In order to examine those small-scale effects in the context of mountainous watersheds, Sarah is building and running a high-resolution integrated model of a small, meadow-dominated site within the East River watershed.