Volcanic Plume Detection Alert System utilizing data from the Atmospheric Infrared Sounder

Volcanic eruptions can release large volumes of sulfur dioxide (SO2) gas and volcanic ash, posing a threat to both populations on the ground and to aviation. Tracking of these plumes is of critical importance. Sulfur dioxide and dust browse products derived from AIRS observations can indicate the possibility of volcanic activity and help track the movement of volcanic plumes. AIRS data are already utilized in volcanic plume decision support at both the Volcanic Ash Advisory Center (VAAC) in Washington D.C. and at the EUs Support to Aviation Control Services (SACS) which in turn supports the VAAC in Toulouse, France. An automated detection system for SO2 developed at JPL provides alerts, imagery, an event archive and now a new overlay tool to compare SO2, dust, clouds, visible and IR information. The alert system monitors near real-time (NRT) AIRS Level 1B data granules using an algorithm based on the AIRS SO2 brightness temperature difference (BT_diff_SO2) product. Upon detection of a potential SO2 plume, the system generates a suite of visualizations of BT_diff_SO2, dust score, total cloud fraction, cloud top height, IR brightness temperature (at 830 wavenumbers) and for daytime acquisitions the AIRS VIS image. Available in formats suitable for Google Earth and GIS systems, the AIRS browse images are displayed on a dynamically generated web page that contains contextual information, a custom link to NASA Worldview pre-loaded with select Worldview layers, links to additional resources, and access to an archive of previous detections. With challenges that include tuning the alert system to reduce false positives and creating image products that communicate successfully, the system is designed to create an informative and accurate detection system that can be used as an additional resource to decision makers concerned with tracking volcanic plumes. The talk will include a demonstration of the AIRS volcano rapid response web page, event archive, overlay tool and alert subscription service. A high level overview of the detection algorithm will also be provided.