Satellite volcanic ash cloud detection and quantification

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Volcanic ash has been proved to have a profound effect on the operation of both civil and military aviation. Airspace used by aviation is managed operationally using two primary tools: advection-diffusion dispersion models, driven by volcanic and meteorological source terms and satellite remote sensing. The first offers a prediction, vital for flight planners, but forward projection increases uncertainty. The latter, whilst being imperfect, provides snapshots that, at the very least, may be used to validate predictions. One of the major problems with satellite imagery is that any observations are integrated along the line of sight. As we transition from safe-to-fly thresholds to a dose-based approach to hazard management observations in three dimensions become critical. The primary purpose of this activity is to develop a thermal infrared (TIR) imaging instrument for a University of Bristol CubeSat that will be able to map and reconstruct ash clouds in three dimensions. The camera would be used in a 'point and stare' (flashlight) mode to use multiple viewing angles to image the three-dimensional structure of the ash cloud. The PhD will initially comprise of an assessment of the science and mission requirements, based upon previous work undertaken at Bristol in collaboration with the Rutherford-Appleton Laboratory, and then the elaboration of a conceptual design for the spacecraft imager. Once the conceptual design is finalised, a detailed design of a breadboard using off the shelf components will be finalised. The design will require mechanical, electrical, optical and software analysis and will be based as far as possible on existing products. This breadboard will be built, tested and miniaturised to be flown on a balloon for altitude testing and on a UAV over at least one erupting volcano in Central America. The image data will be processed using 3D reconstruction techniques such as SLAM, currently being developed from optical imagery by Dr. Andrew Calway's group in computer science. This work is linked to research on drone imaging of volcanos being planned as part of the CASCADE programme led by Professor Arthur Richards and Dr Tom Richardson and may be eligible for funding under this programme. The research question will be: is it possible to provide 3D reconstruction of a volcano ash cloud using a miniature space-based thermal camera in 2 wavelengths?