Coupled effects of surface erosion and magma intrusion on magmatic hazards under a changing climate

The impact of rainfall-driven erosion on the evolution of magmatic systems and, ultimately, on volcanic activity, is an emerging topic of critical importance in the context of the ongoing climate crisis. While tectonic forces control magma intrusion through the crust, climatic factors (i.e., rainfall) may influence magma ascent and contribute to volcanic eruptions. Here, we present a set of innovative analogue models integrating uplift driven by magma intrusion, and surface processes triggered by a rainfall system. By varying magma injection rates and rainfall intensities, we examine surface morphology under different conditions. Our models reveal that the topographic elevation, a proxy for the effectiveness of surface processes, does not correlate with increasing rainfall intensity. Only under heavy rainfall rates, the system significantly erodes and relocates material from the top of the rising dome to its rim, likely modulating magma ascent. Under this condition, the resulting topographic dome shows the lowest elevation and the greatest accommodation volume. We then speculate that the erosional unloading of the overburden could increase the magmatic chamber's force to cause uplift. Ultimately, although the present work represents an initial study, we emphasize how extreme rainfall events might drive magmatic systems toward a more critical state.