Spatio-temporal rainfall variability and its impacts on the hydrological response of nature-based solutions

ABSTRACT

The high spatio-temporal variability of precipitation makes the hydrological responses of nature-based solutions (NBS) indeterminate. Hence, this study investigated the hydrological responses of a semi-urban catchment and three NBS scenarios concerning different spatio-temporal rainfall data from both C-band radar and X-band radar. Multi-Hydro, the fully-distributed and physically-based hydrological model, is employed to study the spatio-temporal rainfall variability and the resulting hydrological impacts on the NBS scenarios. The scale-independent indicator of maximum probable singularity (γ_s) within the Universal Multifractals (UM) framework is used to quantify the spatio-temporal variability of rainfall and catchment responses across scales. The main results show that the hydrological performances of the NBS scenarios can be largely underestimated or overestimated because of the spatio-temporal rainfall variability, with a relative error ranging from −91% to 199%, and NBS can effectively reduce surface runoff across scales, which is characterised by a lower γ_s.

KEYWORDS:

• Spatio-temporal variability
• Nature-based solutions
• Universal Multifractals
• hydrological responses

Acknowledgements

The first author greatly acknowledges the financial support by the TIGA-CHEF project. The authors acknowledge the Chair “Hydrology for Resilient Cities” (endowed by VEOLIA), for partial financial support and for providing the C-band radar data. The authors acknowledge Saint Quentin-en-Yvelines agglomeration community for providing the data of Guyancourt catchment.

Disclosure statement

No potential conflict of interest was reported by the author(s).

Additional information

Funding

This work was supported by the TI(GA)-CFHF.