Application of WRF-Hydro for Retrospective Seasonal Streamflow Simulations using WRF-Hydro at Lake George, New York

Lake George is a glacial, oligotrophic water body with pristine water quality. Recently, it has experienced ecological changes due to the influx of invasive species, increasing levels of salt from road de-icing agents as well as nutrient loading via storm water runoff. One of the purposes of this paper is to present analyses of retrospective seasonal simulations of streamflow in the Lake George, New York watershed for the different seasons of 2018-2019.

In order to study these changes, a framework comprising of a modeling system and observations in the Lake George watershed is used. The present work focuses on the following components: (a) a recent release of the WRF-Hydro community hydrological model (b) a comprehensive observational data set consisting of streamflow, soil moisture and weather parameters; (c) comparison of snow predictions from a daily, operational 333m-resolution, 36-hour weather forecasts using the community WRF v3.9.1 model with National Operational Hydrologic Remote Sensing Center (NOHRSC) gridded products; (d) manual calibration of soil and hydrological parameters and their impact on seasonal streamflow and soil moisture; and (e) impact of manual calibration on storm events during this period. The WRF-Hydro simulations are performed in standalone mode using gridded routing at 41m resolution with forcing provided by the aforementioned WRF runs and NLDAS-2. The authors will present preliminary results, including more recent efforts to estimate road salt loading via runoff into Lake George.