Speakers:  Sean Horvath, water resources and climate scientist, Lynker
                     Zach Wills, chief technical officer, Lynker

Topic:   The Next Generation Water Resources Modeling Framework (NextGen): Advancing the National Water Model

The National Water Model (NWM) is a hydrologic modeling framework that produces forecasts and reanalysis datasets for the continental United States (CONUS) as well as southern Alaska, Hawaii, Puerto Rico and the US Virgin Islands (OCONUS). It is a crucial tool that provides continuous, 24/7 guidance on streamflow and other hydrologic components. Currently at version 3.0, the NWM has been rapidly enhanced through a partnership between the National Weather Service (NWS) Office of Water Prediction (OWP), the National Center for Atmospheric Research (NCAR), the National Centers for Environmental Prediction (NCEP), and academic and private partners. Despite its strengths, the NWM has limitations in terms of model flexibility, spatial heterogeneity, and the integration of diverse hydrologic processes.

To address these challenges, the Next Generation Water Resources Modeling Framework (NextGen) has been developed. NextGen is a model-agnostic, modular system designed to support large-scale hydrologic modeling with mosaics of model formulations tailored to dominant processes in specific basins or regions. Unlike traditional models, NextGen does not require access to the source code or the need to compile models and the framework together for each task, provided they comply with widely accepted standards such as the Community Surface Dynamics Modeling System's Basic Model Interface (BMI) and the Open Geospatial Consortium's WaterML (version 2) Hydrographic Features (HY_Features) data model. Compliance with these standards allows the framework to treat models in a plugin-like fashion. The BMI facilitates model coupling and execution across various programming languages, enabling interoperability and reducing the complexity of model integration. The hydrofabric focused tools allow areas to be extracted from the continental domains.

This framework aims to improve hydrologic forecasting by enabling more accurate and efficient simulations through unparalleled flexibility in model coupling and execution.

Bio: Sean Horvath is a water resources and climate scientist with expertise in spatiotemporal hydrologic and cryospheric science. His doctoral and postdoctoral research at the University of Colorado Boulder and the University of Maryland/NASA Goddard focused on studying Arctic sea ice to improve predictive capabilities on seasonal to subseasonal time scales. This work involved exploring innovative approaches to modeling and predicting sea ice, with a focus on sea ice variability, and included research on the role of diminishing sea ice on climate variability in the northern hemisphere and feedback mechanisms in the coupled sea ice – ocean – atmosphere system. He also worked on developing a novel approach to use passive microwave satellite data of brightness temperatures and skin and surface air temperature to detect melt and freeze events in the snow pack over sea ice which are important indicators of the survivability of sea ice. His current work at Lynker focuses on a variety of water resource related issues with an emphasis on developing and integrating a 1D hydrologic & hydraulic stream routing module for the Next Generation Water Resources Modeling Framework.

Bio: Zach Wills is the Lynker Division 2 Chief Technical Officer and is in charge of the computational implementation of environmental modeling at scale. Currently this involves expanding computational scaling from laptops to supercomputers, and beyond even those limitations to cloud implementations. Zach presented this year at AGU for the NOAA Integrated Ocean Observing System on the layered system interactions and synergies of people, compute, software and modeling as it pertains to NOAA’s new Coastal Modeling Sandbox. Before Lynker, Zach spent nearly a decade pioneering the computational infrastructure for NOAA at the National Water Center, and previous to that worked doing digital investigation at a Law firm and before that at Apple. Zach holds a BA in International Studies from the University of Missouri.