Publications

Schneider, KE; Hogue, TS (2022). Calibration of a hydrologic model in data-scarce Alaska using satellite and other gridded products. JOURNAL OF HYDROLOGY-REGIONAL STUDIES, 39, 100979.

Abstract
Study Region: Alaska and hydrologically connected portions of Canada Study Focus: Rugged terrain and harsh conditions make observational hydroclimatic data, espe-cially runoff data, extremely limited across most of Alaska. Consequently, many previous hy-drologic studies in Alaska have focused on smaller-domain trends, where pockets of hydroclimatic observations are clustered. Using a combination of reanalysis and remotely sensed gridded products, we develop a calibration framework for a monthly resolution water budget model, over the entire Alaskan domain, that does not rely on runoff. The domain is comprised of distributed model response units (MRUs), each representing a Hydrologic Unit Code 12 basin. We use a Fourier Amplitude Sensitivity Test (FAST) to inform a two-step calibration process; first cali-brating to actual evapotranspiration and then to fractional snow-covered area (fSCA), resulting in a range of parameter solutions for each MRU. New Hydrological Insights for the Region: Using this framework, the model performs best in the moderate to dry Alaskan interior; in the absence of glaciation and where permafrost is generally not continuous. Modelled runoff for recent decades shows increased runoff trends at lower lati-tudes and slightly decreased runoff trends at higher latitudes within the Alaskan domain. These findings reveal that reliance upon non-runoff fluxes for model calibration is viable in this cold region and that better characterization of hydroclimatic data is necessary to improve confidence in cold region modeling studies.

DOI:
10.1016/j.ejrh.2021.100979

ISSN:
2214-5818