Fair and safe allocation of natural resources for the Euro-Mediterranean area, especially for semi-arid regions, strongly relies on the adoption of WEFE (Water Energy Food Ecosystem) Nexus strategies. Transitioning to WEFE Nexus requires novel quantifiable assessment for interlinked analysis of the four WEFE sectors. Several indicator-based tools exist for agricultural sustainability at the farm scale. This contribution investigates on the application of IDEA method for WEFE Nexus approaches.

This short paper is the preface of the PIAHS volume of the IAHS/UNESCO FRIEND-Water conference of Cotonou in November 2021.

The sensitivity of a geomorphology-based hydrological modelling is evaluated according to four DEMs from 5 m to 50 m resolution in Brittany, France. A set of 8 basins (5–565.7 km²) is used in a pseudo-ungauged context to explore the potential of Prediction in Ungauged Basin (PUB). The results show that a coarse-worldwide DEM such as SRTM (25 m) supported similar performances than the finer one available from the French mapping institute.

The 8th Global FRIEND conference highlighted the advance in hydrological science and innovation in water management. 52 accepted papers cover study areas in precipitation and climate impact; observation, analysis and simulations of hydrologic processes; floods in the changing environments; drought monitoring and analysis; water resources and environmental impacts. The outcome of the conference presented in the proceedings will be shared and discussed widely among UNESCO IHP networks.