H119-04
A Multivariate Hydrologic Benchmark for the WRF-Hydro-Based NOAA National Water Model over Experimental Alaskan Watersheds
Friday, 11 December 2020: 07:12
Virtual
Aubrey L Dugger1, Katrina E Bennett2, Vladimir A Alexeev3, Alec P Bennett4, Matthew Casali5, Jessica E Cherry6, Brian A. Cosgrove7, Carl Dierking8, Trude Eidhammer1, Thomas Enzminger9, David J Gochis1, Joe Grim10, Benjamin Crane Johnson11, Scott Lindsey11, Emily Niebuhr12, Kevin Michael Sampson13, David P Streubel14, Wanru Wu15 and Yongxin Zhang16, (1)National Center for Atmospheric Research, Boulder, CO, United States, (2)Los Alamos National Laboratory, Earth and Environmental Sciences, Los Alamos, NM, United States, (3)Univ Alaska Fairbanks, Fairbanks, AK, United States, (4)University of Alaska Fairbanks, Fairbanks, AK, United States, (5)University Corporation for Atmospheric Research, Boulder, United States, (6)National Weather Service, Alaska Pacific River Forecast Center, Anchorage, United States, (7)NOAA/NWS/OHD, Silver Spring, MD, United States, (8)University of Alaska Fairbanks, Geographic Information Network of Alaska, Fairbanks, AK, United States, (9)Univ of Colorado Boulder, Boulder, CO, United States, (10)NCAR, Boulder, CO, United States, (11)NOAA National Weather Service Alaska-Pacific River Forecast Center, Anchorage, AK, United States, (12)NOAA Arctic Testbed & Proving Ground, Anchorage, United States, (13)National Center for Atmospheric Research, Research Applications Laboratory, Boulder, CO, United States, (14)NWS Alaska River Forecast Ctr, Hage, United States, (15)NOAA/NWS/OHD-Hydrology Lab, Silver Spring, MD, United States, (16)NCAR-Rsrch Applications Lab, Boulder, CO, United States
Abstract:
The NOAA National Water Model (NWM) is a U.S. operational water forecasting system, predicting all major components of the terrestrial water cycle over the Contiguous U.S., Hawaii, Puerto Rico, and the U.S. Virgin Islands. The State of Alaska presents a new challenge for the operational NWM to extend forecasting capabilities into an area dominated by cold-regions hydrology. Until now, processes critical to conditions like deep snowpack, glaciers, frozen soils, permafrost, and river/lake ice have not been extensively explored within the NWM framework.
As part of a collaborative, multi-institutional effort, a prototype of the NWM has been implemented over portions of South-Central and Central Alaska. The WRF-Hydro hydrological modeling system, developed by the National Center for Atmospheric Research (NCAR) as a coupling framework for atmospheric, land surface, and hydrological models, has served as the backbone of the operational NWM since its inception in 2016. Here, we present an assessment of WRF-Hydro model performance over the Cook Inlet, Copper River, and Chena River watersheds. WRF-Hydro was configured using a 1-km resolution instance of the NoahMP land surface model, 250-m resolution lateral terrain routing modules, and National Hydrography Dataset (NHD) vector-based river and lake routing models. The model domains were forced with atmospheric inputs from NCAR's Weather Research and Forecasting (WRF) model, NOAA's Analysis of Record for Calibration (AORC), and Alaska-Pacific River Forecast Center's precipitation data products for 3-13 years, depending on product availability. We present an integrated assessment of model performance across these watersheds for snow, soil moisture, and streamflow as compared against in-situ and remotely-sensed observations, with a focus on spatial and seasonal patterns in model skill. We also explore how uncertainties in precipitation inputs propagate into hydrological prediction in this relatively data-sparse region. This hydrological baseline assessment is informing model development priorities in preparation for the Alaska NWM operational implementation, scheduled for 2022.
