TY  - JOUR
A1  - He, Zhihua
A1  - Unger-Shayesteh, Katy
A1  - Vorogushyn, Sergiy
A1  - Weise, Stephan M.
A1  - Kalashnikova, Olga
A1  - Gafurov, Abror
A1  - Duethmann, Doris
A1  - Barandun, Martina
A1  - Merz, Bruno
T1  - Constraining hydrological model parameters using water isotopic compositions in a glacierized basin, Central Asia
JF  - Journal of hydrology
N2  - Water stable isotope signatures can provide valuable insights into the catchment internal runoff processes. However, the ability of the water isotope data to constrain the internal apportionments of runoff components in hydrological models for glacierized basins is not well understood. This study developed an approach to simultaneously model the water stable isotopic compositions and runoff processes in a glacierized basin in Central Asia. The fractionation and mixing processes of water stable isotopes in and from the various water sources were integrated into a glacio-hydrological model. The model parameters were calibrated on discharge, snow cover and glacier mass balance data, and additionally isotopic composition of streamflow. We investigated the value of water isotopic compositions for the calibration of model parameters, in comparison to calibration methods without using such measurements. Results indicate that: (1) The proposed isotope-hydrological integrated modeling approach was able to reproduce the isotopic composition of streamflow, and improved the model performance in the evaluation period; (2) Involving water isotopic composition for model calibration reduced the model parameter uncertainty, and helped to reduce the uncertainty in the quantification of runoff components; (3) The isotope-hydrological integrated modeling approach quantified the contributions of runoff components comparably to a three-component tracer-based end-member mixing analysis method for summer peak flows, and required less water tracer data. Our findings demonstrate the value of water isotopic compositions to improve the quantification of runoff components using hydrological models in glacierized basins.
KW  - Water stable isotope
KW  - Isotope-hydrological integrated modeling
KW  - Quantification of runoff components
KW  - Glacierized basins
Y1  - 2019
U6  - https://doi.org/10.1016/j.jhydrol.2019.01.048
SN  - 0022-1694
SN  - 1879-2707
VL  - 571
SP  - 332
EP  - 348
PB  - Elsevier
CY  - Amsterdam
ER  -