CUAHSI's 2017 Fall Cyberseminar Series:

Towards a Global Integrated Hydrology Platform: Perspectives and Advances in Large-scale Modeling

Wednesdays, September - October at 12:00 p.m. EDT

Host: Reed Maxwell, Rowlinson Professor of Hydrology (Colorado School of Mines)

Questions critical to human water use and environmental change increasingly require approaches that incorporate interconnected hydrologic processes and bridge a wide range of spatial scales. These needs have pushed models forward in both process complexity and spatial extent. Hydrology models that include connections between groundwater, surface water, land surface processes, human water use and even the atmosphere are now running at high resolution over continents and across the globe. This seminar series highlights recent research from four groups working to advance large-scale hydrologic modeling. Starting with a global perspective, these seminars will discuss various success stories and challenges as the hydrology community advances an integrated perspective of Earth’s freshwater.

Dates, Speakers and Topics:

  • September 20: Global hydrology and water resources: review, challenges and directions | Marc Bierkens (Utrecht University)
  • September 27: Groundwater-to-atmosphere simulations including human water use at the continental scale | Stefan Kollet (Research Center Jülich and Bonn University)
  • October 4: Update on the U.S. National Water Model, recent comparisons to observations | David Gochis (NCAR)
  • October 11: Evaluating groundwater surface water interactions across the Continental U.S. using an integrated hydrologic model | Laura Condon (Syracuse University)

Presentation Abstracts:

  • Marc Bierkens (Utrecht University) on September 20, 2017 at 12:00 p.m. EDT

    Global hydrology and water resources: review, challenges and directions

    Since the landmark paper of Eagleson (1986), announcing the emergence of global hydrology, the field of global hydrology and water resources has developed tremendously. Hydrological submodels of varying complexity are now part of global climate models, of models calculating global terrestrial carbon sequestration, of earth system models, and even of integrated assessment models. This seminar, which is based on a recent review paper (Bierkens, 2015), reviews the current state of global hydrological and water resources modeling, discusses past and recent developments, and extrapolates these to future challenges and directions. It start with describing the history of global hydrological model development in three established domains: atmospheric modelling, global water resources assessment and dynamic vegetation modelling. Next, a genealogy of global hydrological models is given. Thereafter, recent efforts to connect model components from different domains  are reviewed with special reference to multi-sectoral inter-comparison projects. Also, new domains of application are identified where global hydrology is now starting to become an integral part of the analyses. Finally, inspired by these new domains of application, persistent and emerging challenges are identified (including hyper-resolution modelling) as well as the directions global hydrology and water resources is likely to take in the coming decade and beyond.

    Bierkens, M. F. P. (2015), Global hydrology 2015: State, trends, and directions, Water Resources Research 51, 4923–4947.
    Eagleson, P. (1986), The emergence of global-scale hydrology, Water Resources Research 22, 6S–14S.

  • Stefan Kollet (Research Center J├╝lich and Bonn University) on September 27, 2017 at 12:00 p.m. EDT

    Groundwater-to-atmosphere simulations including human water use at the continental scale

    In the webinar, we will take a tour from groundwater across the land surface into the atmosphere inspecting important interfaces, and how these interfaces are treated theoretically and technically in coupled models of the terrestrial water and energy cycle. The human impact with regard to groundwater pumping and irrigation will be introduced, adding even more complexity to an already extremely intricate biogeophysical problem. Major challenges and simplifying assumptions will be discussed that are a prerequisite for interpreting simulation results and assessing uncertainty. Our tour will serve as the basis for introducing the Terrestrial Systems Modeling Platform (TerrSysMP) including simulation examples, which demonstrate the importance of closing the terrestrial water and energy cycle from groundwater into the atmosphere.

  • David Gochis (NCAR) on October 4, 2017 at 12:00 p.m. EDT

    Update on the U.S. National Water Model, recent comparisons to observations

    The NOAA National Water Model became fully operational in August of 2016 providing real-time, high resolution forecasts of key hydrologic variables such as soil moisture, shallow groundwater, evapotranspiration, snowpack and surface runoff. It also provides streamflow forecasts for over 2.7 million river reaches within and tributary to the coterminous U.S.  Since becoming operational there have been 2 significant upgrades to the modeling system that have targeted known shortcomings in the representation of certain hydrologic variables. This seminar will provide an updated overview of the National Water Model, which is based on the community WRF-Hydro modeling system, and provide examples of several different operational and experimental forecast products that are currently being generated and evaluated. Particular emphasis in this talk will focus on multi-variate verification of National Water Model simulations and forecasts that have been conducted to date. Links to ongoing collaborative research with many academic and agency partners will also be discussed.

  • Laura Condon (Syracuse University) on October 11, 2017 at 12:00 p.m. EDT

    Evaluating groundwater surface water interactions across the Continental U.S. using an integrated hydrologic model

    Large-scale, high-resolution hydrologic simulations provide new opportunities to address outstanding scientific questions in complex integrated systems. We use a fully integrated hydrologic model to simulate physically based dynamic interactions from the groundwater through the land surface at 1 km2 spatial resolution across more than 6,000,000 km2 of continental US.  This is accomplished with ParFlow-CLM, which incorporates 3D variably saturated groundwater flow, overland flow and a fully coupled water energy balance at the land surface.  Model outputs are used to characterize groundwater surface water exchanges across a wide range of hydroclimatic settings and spatial scales. We evaluate patterns in groundwater depth, land energy partitioning and basin productivity to identify areas of strong interaction between the surface and subsurface.  Results illustrate the importance of lateral groundwater flow in supporting surface water availability and moderating temporal variability in many settings. Predevelopment and groundwater pumping scenarios are also compared to evaluate the sensitivity of land energy fluxes to large-scale declines in groundwater storage. Using these scenarios, we demonstrate how human alterations to groundwater configuration can propagate through hydrologic systems and impact streamflow and land energy fluxes.