Effect of spatiotemporal variation of rainfall on dissolved oxygen depletion in integrated catchment studies

This study addresses the effect of spatial and temporal resolution of rainfall fields on the performance of a simplified integrated catchment model for predicting dissolved oxygen concentrations in a river. For that purpose we propose a procedure to generate rainfall products with increasing spatial information at different time step accumulations (10’, 30’ and 60’) at the spatial support of lumped urban catchment systems. Using a rain gauge network and single-polarization C-Band Radar data we generate 4 rainfall products; 1) Homogeneous rainfall from a single rain gauge, 2) Block kriging interpolation from a network of 13 rain gauges, 3) Averaged Radar estimation and 4) Universal block kriging from a rain gauge network and using Radar as an external covariate. Comparison of the model predictions with monitoring data in the river showed a low sensitivity to the temporal scales proposed and a relative improvement with increasing spatial information linked to the climatological characteristics of the storm period.