| Remote sensing has been used as a tool to monitor and quantify airborne volcanic ash for several decades. As algorithms and sensors (both ground- and satellite-based) increase in sensitivity and complexity we can learn more about fragmentation, transport, deposition and remobilisation processes using these types of observations. Recent eruptions in Iceland have brought together a wealth of different data on ash processes using, a combination of remote and direct sampling and dispersion modelling. I will present the current state of knowledge on remote sensing of volcanic ash, include recent advances in detection and quantification of particle size information and discuss where the field is heading in the next five years. |