CIMSS Satellite Blog

Soumi NPP VIIRS true-color RGB images [click to enlarge]

The Popocatepetl Volcano in Mexico began erupting at 0546 UTC on 20 January 2016 (Washington VAAC message). The volcanic plume was evident on Suomi NPP VIIRS true-color Red/Green/Blue (RGB) images on 23, 24, and 25 January, as viewed using the SSEC RealEarth web map server (above).

Nighttime images of Suomi NPP VIIRS Shortwave Infrared (3.9 µm), Longwave Infrared Window (11.45 µm), and Day/Night Band (0.7 µm) images at 0817 UTC on 25 January (below, courtesy of William Straka, SSEC) revealed the hot spot of the erupting volcano summit (orange pixels), and ample illumination from the Moon allowed the plume to be seen on the Day/Night Band image.

Suomi NPP VIIRS Shortwave Infrared (3.9 µm), Longwave Infrared Window (11.45 µm), and Day/Night Band (0.7 µm) images [click to enlarge]

A legacy product for use in the detection of volcanic ash plumes is the Infrared “split window” (11-12 µm) brightness temperature difference product (below), which showed the plume streaming eastward to northeastward during the 24-25 January period.

Terra/Aqua MODIS and Suomi NPP VIIRS Infrared “Split Window” (11-12 µm) Brightness Temperature Difference product images [click to enlarge]

Taking advantage of the multispectral imagery available from the MODIS and VIIRS instruments, quantitative products such as Ash Height, Ash Loading, Ash Effective Radius, and Ash Probability from the NOAA/CIMSS Volcanic Coud Monitoring are shown below.

Terra/Aqua MODIS and Suomi NPP VIIRS Volcanic Ash Height product [click to enlarge]

Terra/Aqua MODIS and Suomi NPP VIIRS Volcanic Ash Loading product [click to enlarge]

Terra/Aqua MODIS and Suomi NPP VIIRS Volcanic Ash Effective Radius product [click to enlarge]

Terra/Aqua MODIS and Suomi NPP VIIRS Volcanic Ash Probability product [click to enlarge]

from CIMSS Satellite Blog http://ift.tt/23uuTxi