Authors: Yi Hong, Cooperative Institute for Great Lakes Research, University of Michigan
Presentation Type: Lightening talk
Title: Challenges and Opportunities for the National Water Model applications Over the Laurentian Great Lakes Region
Abstract: The Laurentian Great Lakes region is home to approximately 30 million people across the United States and Canada. Given its ecological, economic, and cultural significance, the Great Lakes region requires accurate hydrologic predictions for robust water resources management. However, the Great Lakes basin is characterized by crossing international boundaries and large water bodies, which poses challenges to acquiring consistent estimates of hydro-meteorological factors for accurate simulations. To address this challenge, NOAA has expanded its operational National Water Model (NWM) domain into the Canadian portion of the Great Lakes basin. WRF-Hydro is the backbone of the NWM v2.1.
In this context, the present study aims to comprehensively evaluate the accuracy of the operational NWM V2.1 over the Great Lakes region, and to assess opportunities to advance the NWM to a next-generation water resources modeling framework over the Great Lakes basin. To this end, we first collected and analyzed reanalysis (since 1979) and long-range forecast (up to 30 days) of all simulated stream flows over the Great Lakes region. The performance of NWM V2.1 was then evaluated by comparing simulations with gauge observations for different U.S. and Canadian sub-basins; moreover, streams flowing into each of the Great Lakes were aggregated and evaluated to assess the capacity of NWM for water balance simulations. The results indicated that NWM V2.1 has shown acceptable performance over most of the U.S. sub-basins; however, the accuracy over Canadian sub-basins, particularly for Lake Superior, needs to be improved. In addition, we have made recommendations to enhance modeling skills that could improve the total inflow simulations for each of the Great Lakes for water balance perspectives