Relative to satellite-derived meteorological cloud properties, quantitative satellite-derived volcanic ash cloud properties do not have a long heritage in operational applications. To facilitate operational readiness, in response to the demand for quantitative ash cloud products from the aviation user community, an organized international effort is needed to benchmark the accuracy of various satellite products under a large variety of conditions and establish best scientific practices for operational applications. Under the World Meteorological Organization (WMO) Sustained Coordinated Processing of Environmental Satellite Records for Nowcasting (SCOPE-Nowcasting) initiative, the first component of an international effort to benchmark and inter-compare volcanic ash products derived from satellite measurements was completed in 2015. Detailed information on the 2015 activity is available:
2015 inter-comparison website: http://cimss.ssec.wisc.edu/meetings/vol_ash15/
WMO Report on 2015 activity: http://www.wmo.int/pages/prog/sat/documents/SCOPE-NWC-PP2_VAIntercompWSReport2015.pdf
The successful 2015 WMO Inter-comparison of Satellite-based Volcanic Ash Retrieval Algorithms activity broadly revealed that the accuracy of satellite-based volcanic ash products is a strong function of the retrieval methodology, satellite sensor capability, and scene complexity. In order to benchmark the various retrieval methodologies and satellite sensors as a function of the scene attributes (e.g. number of cloud layers, type of underlying surface, ash composition, etc.) and ascertain which methodologies and scientific practices are best suited for operational applications, the inter-comparison activity needs to be advanced further using the recommendations from the 2015 inter-comparison report as a guide.
A second WMO SCOPE-Nowcasting inter-comparison activity is being undertaken in 2018 with the following objectives.
1) Analysis of certain cases (from 2015 activity) in greater detail in order to better understand ash detection and retrieval differences and sensitivities
2) Assessment of volcanic ash products generated from “next generation” satellite sensors, such as Himawari-8
3) Assessment of product performance on ice rich umbrella-like volcanic clouds
4) Documenting advances in satellite-derived volcanic ash products over the last 3 years
5) Creating a consensus “road map” for meeting the increasing demand for high quality satellite-derived volcanic ash products for operational applications.
In support of the 2018 WMO SCOPE-Nowcasting volcanic ash inter-comparison activity, a workshop, hosted by INGV, will be held 8-12 October 2018 in Catania, Italy.