Influence of climate change on magmatic processes: What does geodesy and modeling of geodetic data tell us?

Abstract

Anthropogenic global climate change is causing ice mass loss in all glacierized regions in the world. Iceland provides conditions that make it an efficient laboratory to study the effects of retreating glaciers on magmatic activity, as retreating glaciers currently cover approximately 10% of Iceland and 50% of its active volcanoes. Retreat of glaciers results in unloading and glacial isostatic adjustment as observed well in Iceland by extensive GNSS (Global Navigation and Satellite System) and Interferometric Synthetic Aperture Radar (InSAR) geodetic measurements. The unloading results in more magma being generated in the mantle through decompression melting. It also induces stress changes in the crust that may affect magma migration and the stability of existing magma bodies. Large uncertainties are involved in evaluating the effects, as they depend on many factors such as the detailed structure of magmatic systems and the rheology of host rock and magma.