Chapter 13 - Applications of Satellite Observations of Volcanic Ash in Atmospheric Dispersion Modeling

Abstract

Satellite observations have been instrumental in the detection and monitoring of hazardous airborne volcanic ash and in constraining atmospheric dispersion modeling for ash transport forecasting. Here, we provide an overview of how they are used by modelers to interpret and evaluate output from volcanic ash dispersion and transport models and also inform the source terms used in those models. We include instances where satellite observations and model output have been used complementarily to glean information about ash episodes, and we give detailed examples of the use of observations in data assimilation. Using these examples, we show how satellite observations have enabled the volcanic ash community to improve forecasts and better characterize uncertainty in model eruption source parameters. The dispersion modeler should be aware of the uncertainties and limitations attributable to satellite observations of ash, and how assumptions can affect interpretation of the observations. We give a brief discussion of some of these issues.