A conceptual hydrological model of semiarid Andean headwater systems in Chile

Semiarid Andean headwaters are key components of the hydrological system of north-central Chile as this is the main source of runoff which supports ecosystems and population located downstream. This study develops a conceptual hydrological model of the Chilean semiarid Andes headwaters, based on an integrative critical analysis of the current state of published research in the region. We combine a plethora of literature focused on isolated hydrological units including extensive literature on glacier and snowpack hydrological processes and less abundant literature on permafrost landforms, groundwater dynamics and other hydrological features. Among others, we identify important knowledge gaps related to the hydrogeomorphological understanding of permafrost area and its interaction with groundwater, as well as deep aquifer recharge and circulation. These two research topics are necessary next steps to better constrain model predictions of catchment response to future climatic scenarios associated with decreasing water contribution from glaciers and precipitation.