Dependence of rainfall-runoff model transferability on climate conditions in Iran

ABSTRACT

This study investigates the potential differences between spatial and temporal transferability of the Hydrologiska Byråns Vattenbalansavdelning (HBV) rainfall-runoff model parameters in 576 Iranian catchments. Our goal is to determine how parameter transferability is affected by (a) parameter transfer modes (temporal or spatial) and (b) different climate conditions. In the temporal mode, we make decisions in each catchment based on a benchmark baseline that accounts for the seasonality of flows. In the spatial mode, we examine physical similarity and spatial proximity methods. The main conclusions are that: (1) the HBV model struggles to beat the benchmark in lowland catchments; (2) under stationary conditions, rainfall-runoff models have greater temporal transferability than spatial transferability; (3) under non-stationary climate conditions, the number of catchments that perform best in terms of temporal transferability is smaller than in stationary climate conditions; and (4) the rainfall-runoff model has better transferability from drier to wetter conditions.

KEYWORDS:

• rainfall-runoff model
• benchmark baseline
• spatial and temporal transferability

Editor A. Fiori Associate Editor K. Kochanek

Editor A. Fiori Associate Editor K. Kochanek

Acknowledgements

The authors are grateful to Iran Energy Ministry, Iran Meteorological Organization, and Water Resources Investigation consulting engineers for their cooperation and provision of required data. We also thank Dr Jan Magnusson, whose detailed comments led to significant improvements to the original manuscript.

Disclosure statement

No potential conflict of interest was reported by the authors.

Data availability

https://www.dropbox.com/s/rjog04at8gd9ute/Data.zip?dl=0