"w_tom" wrote

Cloud to ground lightning creates a unique RF signature. By
recording these radio waves and by using time from GPS satellites to
corrdinate those receptions, then the NLDN could pinpoint those ground
strikes. When too many ground strikes occur, the network tends to
become overloaded; does not detect all strikes.

In a gross simplification, cloud to ground flashes produce disturbances in
the LF and VLF EM bands. They are received over very long distances, so
they are easier to get a map of over a complete region, even with a sparse
location of sensors. Probably why it is desirable.

Cloud to cloud flashes are mainly in the VHF range, and therefore are line
of sight.

For a very complete explanation, see
https://www.thelightningpeople.com/htm/about/events/ildc/ildc2000/docs/03_CUMMINS.pdf
--
Jim in NC