Title: Sub-grid snow variability in stream flow modelling of an Alpine catchment
Authors: Shailesh Kumar Singh
Addresses: National Institute of Water and Atmospheric Research, Christchurch 8011, New Zealand
Abstract: The spatial variability of snow within a catchment can have a great influence on hydrological response of the catchment. Accounting sub-grid variability within hydrological models will improve simulations. This paper investigates the effect of sub-grid snow variability parameterisation on stream flow modelling in an alpine catchment. The TopNet hydrological model was applied to a catchment in the Southern Alps, New Zealand. The model was calibrated for range of sub-grid snow variability parameters. The parameter value that resulted in the best calibration was compared to physically derived values. The full range of sub-grid snow variability values tested led to log-Nash Sutcliffe values ranging 0.66-0.74, indicating that the model is relatively sensitive to the sub-grid snow variability. The sub-grid snow variability parameter that led to the best calibrated model agreed well with observations. This result indicates that inclusion of the parameter improves the physical realisation of the model for steep alpine catchments.
Keywords: sub-grid snow variability; hydrological responses; TopNet.
DOI: 10.1504/IJHST.2017.086954
International Journal of Hydrology Science and Technology, 2017 Vol.7 No.3, pp.268 - 285
Received: 11 Jun 2016
Accepted: 20 Aug 2016
Published online: 03 Oct 2017 *