Constraining groundwater buffering role in mountain catchments

Groundwater has a critical role in mountains regulating hydrological buffering by redistributing water both in space and time. Despite their relevance, it is hard to constrain residence times and flowpaths due to data scarcity and numerical complexity of explicit groundwater model. Here, we use a simplified distributed groundwater model to constrain hydrological buffering metrics in a ∼10,000 km² mountain catchment spanning altitudes from 1,000 to 6,400 m.a.s.l. We calibrate catchment response with hydrometric timeseries and near surface water table pseudo observations derived from landscape proxies including groundwater dependent vegetation and springs. We find that the framework can constrain residence times within some months of variability. The results has implications to provide better estimates of groundwater role in mountain catchments with few data available.