HINT: You can also track the movement of an volcanic ash cloud using USRP

An GR application note,

This aint ment to be a commercial advertise, just FYI what you also can
do with a USRPx

We’re tracking the volcanic ash cloud movement from Island, Grimsvotn
using USRP + TVRX, 137 MHz and 1.7 GHz (downconverter), 4km and 1km
pixel resolution.
Air traffic from Scandinavia to US is rerouted.

Sample (downsampled 1km image) from Sunday, 22 May @ 0635Z

Have fun,