Weaver, Connell

     R. Zehr is serving as coordinator for Tropical Cyclones with the Disaster Management Support Project of the Committee on Earth Observing Systems / Integrated Global Observing Strategy (CEOS/IGOS).  This Project is chaired by Helen Wood (NESDIS).  A draft of an executive summary for the Tropical Cyclone Team has been completed in preparation for the Workshop to be held in Silver Spring, MD, March 31-- April 2, 1998.

     The development of a volcanic ash detection product continues using visible imagery and a combination of the 3.9 µm, 10.7 µm, and 12.0 µm imagery.   Principal component analysis is being run on volcanic ash cases to determine what changes and/or patterns in the combined imagery can be detected and if these features will aid in producing a better volcanic ash detection product.

The following are examples of Volcanic Ash detection over land. (Click on images for full size display.)
 
 

Figure 1: Visible, 10.7 µm - 12.0 µm (4 minus 5 difference) product, reflectivity product, and the combined 3.9/10.7/12.0 product for an ash plume from the Popocatepetl Volcano in Mexico, 14 June 1997 1601 UTC.
 

Figure 2:  Principal component imagery for the same scene as above.  Notice the similarity between the 3.9/10.7/12.0 product and PCI 4.