Advances in the provision of warnings for volcanic ash for aviation in the Australian region

Volcanic ash presents a significant hazard to aviation in the Indonesia/PNG region and warnings for ash are provided by the Darwin Volcanic Ash Advisory Centre under arrangements established as part of the ICAO International Airways Volcano Watch. The warnings provided by the Darwin VAAC are based on an initial report or detection of volcanic ash, an analysis of satellite data to identify and track the ash cloud, and a forecast of the movement of the ash derived from upper level winds and an atmospheric dispersion model. The VAA message is then prepared in the internationally agreed format and disseminated to the aviation industry. Analysis of the satellite data and dispersion model output and preparation of the VAA can be manually intensive and there are a number of uncertainties in this process. This paper will describe current activities in the Bureau of Meteorology that are directed at improving the use of satellite data, improving the use if the ash dispersion model and streamlining the warning preparation process.