A methodology for monitoring and modeling of high altitude Alpine catchments

Abstract

Hydrological monitoring and modeling of high altitude Alpine catchments is of paramount importance. This is difficult, however, given the complex logistics of field campaigns and the need for long-term data. Here, we present a method for long term monitoring of high altitude catchments, which we tested within the Alps of Italy. This includes i) extensive gathering of climate data and hydrological fluxes, ii) high altitude field campaigns, and iii) robust physically based glacio-hydrological modeling, providing full account of ice flow, ice and snow ablation, and stream flows. We present an application of this method based on six years (2009–2014) of field monitoring in the Dosdè catchment, in the Italian Alps (17 km2, average altitude 2858 masl, outlet 2133 masl), nesting 1.90 km2 of glaciers. We demonstrate that i) high altitude Alpine catchments can be monitored in spite of geographical complexity, and ii) a data based approach delivers accurate stream flow estimates and improves our knowledge of flow components in the high altitudes. We then provide some estimates of the recent glaciers’ dynamics, and water resources from this high-altitude catchment, paradigmatic of the recent cryospheric evolution in the Alps of Italy. We estimated an average ice mass loss nearby −1.76E8 m3yr−1, i.e. −20% of the ice mass in 2009, possibly pointing to accelerated glaciers’ down wasting. Instream discharges increased (+0.12 m3s−1y−1); however, this requires further monitoring. We then benchmark our findings against recent studies in the Alps, and other glacierized areas worldwide, displaying similarities in present glaciers’ dynamics. We suggest that our robust, yet flexible approach can be used for glacio-hydrological investigation in Alpine (and generally mountain) rivers, and for conjectures of potential future hydrological cycle under climate scenarios.